# Draft California 2012 Integrated Report( 303(d) List/305(b) Report)

# Supporting Information

## Regional Board 6 - Lahontan Region

Water Body Name: | Amargosa River (Willow Creek confluence to Badwater)
Water Body ID: | CAR6091100020080815165828
Water Body Type: | River & Stream

DECISION ID | 30699 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Arsenic
Final Listing Decision: | Delist from 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Reason for Delisting: | Flaws in original listing
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). However, the decision was changed to a DeList from List because there were flaws in the original data. There is insufficient information to determine if the SAL beneficial use is being impaired for this segment of the Amargosa River, which is naturally high in arsenic.In 2002, the MUN beneficial use was de-designated for the Amargosa River because of the naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. There are no state or federal aquatic life criteria developed to assess whether the aquatic saline habitat present within the Amargosa River is being supported or impaired by arsenic. This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Three lines of evidence, including total and dissolved arsenic in water and arsenic in sediment, are available in the administrative record to assess this pollutant. Two of the dissolved arsenic samples exceed the California Toxics Rule chronic toxicity standard. This standard is based on toxicity tests for marine/estuarine organisms and is not appropriate for inland saline waters, which support different aquatic biota compared to marine ecosystems. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. Only one water sample per year. This sampling frequency does not temporally representative of the conditions in the river, which are characterized by great seasonal and annual variability in flows. 3. Two out of two dissolved arsenic samples exceeded the California Toxics Rule standard and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy. However, as explained above, the standard is inappropriate for inland saline waters. The standard was developed using marine and estuarine organisms, and inland saline waters support different aquatic biota. Inland saline water organisms are adapted to greater extremes of and fluctuations in environmental conditions than marine organisms 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Based on the readily available data and information, the recommendation is to DeList this waterbody pollutant segment at this time.
Regional Board Staff Decision Recommendation: | After review of the available data and information, Lahontan Water Board staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because, although the California Toxics Rule standards are being exceeded, the pollutant is from natural sources, the standards are inappropriate for inland saline waters, and the data are not temporally representative of the conditions in the river, which are characterized by great seasonal and annual variability in flows.

Line of Evidence (LOE) for Decision ID 30699, Arsenic | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46636
Pollutant: | Arsenic
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Concentrations of total arsenic in two samples were 215 and 178 ug/L.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no applicable state or federal saltwater aquatic life standards or criteria for total arsenic in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 30699, Arsenic | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46635
Pollutant: | Arsenic
LOE Subgroup: | Pollutant-Sediment
Matrix: | Sediment
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Chemical monitoring of sediments
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled sediment at this station on March 16, 2005 under the Region 6 SWAMP program. Results were reported as "bed sediment, smaller than 62.5 um, wet sieved, total digestion." The concentration of arsenic was 12 ug/g dry weight.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal standards or criteria for arsenic in sediment in inland saline waters. The Effects Range-Median for arsenic in marine and estuarine sediments is 70 ug/g dry weight; see Long et al. (1995).
Objective/Criterion Reference: | Incidence of adverse biological effects within ranges of chemical concentrations in marine and estuary sediments. Environmental Management. 19, (1): 81-97
| Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sediment sample was collected on March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 30699, Arsenic | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46637
Pollutant: | Arsenic
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 2
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Concentrations of dissolved arsenic in two samples were 207 and 170 ug/L.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | The California Toxics Rule's saltwater aquatic life standards for dissolved arsenic include an acute toxicity limit of69 u/L and a chonic toxicity limit of 36 ug/L.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30506 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | 1, 1, 2-trichloro-1, 2, 2-trifluoroethane | 1, 1-dichloroethane | 2, 4 D methyl ester / 2,4-Dichlorophenoxyacetic acid methyl ester | 2, 4 DB / 4-(2,4-dichlorophenoxy) butyric acid | 2,4-D (2,4-Dichlorophenoxy acetic acid) | 2-Methyl-4-chlorophenoxyacetic acid (MCPA):acetic acid | 2-chloro-4-isopropylamino-6-amino-s-triazine | 2-chloro-6-ethylamino-4-amino-s-triazine | 3-ketocarbofuran | 4(4 chloro-2-methyl phenoxy (MCPB)) butanoic acid | Aciflorfen | Aldicarb | Aldicarb sulfone | Aldicarb sulfoxide | Bendiocarb | Benomyl | Bensulfuron | Bentazon | Bromacil | Bromoxynil | Carbofuran | Chloramben methyl ester | Chlorimuron | Chlorodiamino-s-triazine | Chloropyralid | Chlorothalonil | Cycloate | Dacthal monoacid | Dicamba | Dichloroprop | Diethyl ether | Diisopropyl ether | Dinoseb | Diphenamid | Diuron | Fenuron | Flometuron | Flumetsulam | Hydroxyl carbofuran | Imazaquin | Imazethapyr | Imidacloprid | Linuron | Metalaxyl | Methiocarb | Methomyl | Methyl tert-pentyl ether | Metsulfuron | N-(4-Chlorophenyl) -N' methylurea / Monuron | Neburon | Nicosulfuron | Norflurazon | Oryzalin | Oxamyl (Vydate) | Picloram | Propham | Propiconazol | Propoxur | Siduron | Styrene | Sulfometuron | Tebuthuron | Terbacil | Tert-butyl ethyl ether | Triazone | Tribenuron | Vinyl chloride | meta-para xylenes | o-Xylene
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. Zero of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of one sample exceeded the objective and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 30506, Multiple Pollutants | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46626
Pollutant: | 1, 1, 2-trichloro-1, 2, 2-trifluoroethane | 1, 1-dichloroethane | 2, 4 D methyl ester / 2,4-Dichlorophenoxyacetic acid methyl ester | 2, 4 DB / 4-(2,4-dichlorophenoxy) butyric acid | 2,4-D (2,4-Dichlorophenoxy acetic acid) | 2-Methyl-4-chlorophenoxyacetic acid (MCPA):acetic acid | 2-chloro-4-isopropylamino-6-amino-s-triazine | 2-chloro-6-ethylamino-4-amino-s-triazine | 3-ketocarbofuran | 4(4 chloro-2-methyl phenoxy (MCPB)) butanoic acid | Aciflorfen | Aldicarb | Aldicarb sulfone | Aldicarb sulfoxide | Bendiocarb | Benomyl | Bensulfuron | Bentazon | Bromacil | Bromoxynil | Carbofuran | Chloramben methyl ester | Chlorimuron | Chlorodiamino-s-triazine | Chloropyralid | Chlorothalonil | Cycloate | Dacthal monoacid | Dicamba | Dichloroprop | Diethyl ether | Diisopropyl ether | Dinoseb | Diphenamid | Diuron | Fenuron | Flometuron | Flumetsulam | Hydroxyl carbofuran | Imazaquin | Imazethapyr | Imidacloprid | Linuron | Metalaxyl | Methiocarb | Methomyl | Methyl tert-pentyl ether | Metsulfuron | N-(4-Chlorophenyl) -N' methylurea / Monuron | Neburon | Nicosulfuron | Norflurazon | Oryzalin | Oxamyl (Vydate) | Picloram | Propham | Propiconazol | Propoxur | Siduron | Styrene | Sulfometuron | Tebuthuron | Terbacil | Tert-butyl ethyl ether | Triazone | Tribenuron | Vinyl chloride | meta-para xylenes | o-Xylene
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled organic chemicals at this station on March 18, 2004 under the Region 6 SWAMP program. One sampling result was reported for each of the listed pollutants. All of these pollutants were below the detection level.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no applicable state or federal saltwater standards or criteria for the listed pollutants.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sampling result was reported for each of the listed pollutants from a sample or samples collected on March 18, 2004
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30600 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | 1, 1, 2-trichloro-1, 2, 2-trifluoroethane | 1, 1-dichloroethane | 2, 4 D methyl ester / 2,4-Dichlorophenoxyacetic acid methyl ester | 2, 4 DB / 4-(2,4-dichlorophenoxy) butyric acid | 2,4-D (2,4-Dichlorophenoxy acetic acid) | 2-Methyl-4-chlorophenoxyacetic acid (MCPA):acetic acid | 2-chloro-4-isopropylamino-6-amino-s-triazine | 2-chloro-6-ethylamino-4-amino-s-triazine | 3-ketocarbofuran | 4(4 chloro-2-methyl phenoxy (MCPB)) butanoic acid | Aciflorfen | Aldicarb | Aldicarb sulfone | Aldicarb sulfoxide | Bendiocarb | Benomyl | Bensulfuron | Bentazon | Bromacil | Bromoxynil | Carbofuran | Chloramben methyl ester | Chlorimuron | Chlorodiamino-s-triazine | Chloropyralid | Chlorothalonil | Cycloate | Dacthal monoacid | Dicamba | Dichloroprop | Diethyl ether | Diisopropyl ether | Dinoseb | Diphenamid | Diuron | Fenuron | Flometuron | Flumetsulam | Hydroxyl carbofuran | Imazaquin | Imazethapyr | Imidacloprid | Linuron | Metalaxyl | Methiocarb | Methomyl | Methyl tert-pentyl ether | Metsulfuron | N-(4-Chlorophenyl) -N' methylurea / Monuron | Neburon | Nicosulfuron | Norflurazon | Oryzalin | Oxamyl (Vydate) | Picloram | Propham | Propiconazol | Propoxur | Siduron | Styrene | Sulfometuron | Tebuthuron | Terbacil | Tert-butyl ethyl ether | Triazone | Tribenuron | Vinyl chloride | meta-para xylenes | o-Xylene
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. Because of the limited amount of samples and since there are no state or federal aquatic life criteria for inland saline waters it is not possible to evaluate protection of the SAL beneficial use. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of one sample exceeded the criteria and water quality objective and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded. The U.S. EPA's saltwater aquatic life criteria and saltwater California Toxics Rule (CTR) standards are being used to assess the SAL use for the Amargosa River. However, these criteria and standards are not appropriate for assessment of inland saline waters, which support different aquatic biota compared to the marine ecosystems.

Line of Evidence (LOE) for Decision ID 30600, Multiple Pollutants | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46626
Pollutant: | 1, 1, 2-trichloro-1, 2, 2-trifluoroethane | 1, 1-dichloroethane | 2, 4 D methyl ester / 2,4-Dichlorophenoxyacetic acid methyl ester | 2, 4 DB / 4-(2,4-dichlorophenoxy) butyric acid | 2,4-D (2,4-Dichlorophenoxy acetic acid) | 2-Methyl-4-chlorophenoxyacetic acid (MCPA):acetic acid | 2-chloro-4-isopropylamino-6-amino-s-triazine | 2-chloro-6-ethylamino-4-amino-s-triazine | 3-ketocarbofuran | 4(4 chloro-2-methyl phenoxy (MCPB)) butanoic acid | Aciflorfen | Aldicarb | Aldicarb sulfone | Aldicarb sulfoxide | Bendiocarb | Benomyl | Bensulfuron | Bentazon | Bromacil | Bromoxynil | Carbofuran | Chloramben methyl ester | Chlorimuron | Chlorodiamino-s-triazine | Chloropyralid | Chlorothalonil | Cycloate | Dacthal monoacid | Dicamba | Dichloroprop | Diethyl ether | Diisopropyl ether | Dinoseb | Diphenamid | Diuron | Fenuron | Flometuron | Flumetsulam | Hydroxyl carbofuran | Imazaquin | Imazethapyr | Imidacloprid | Linuron | Metalaxyl | Methiocarb | Methomyl | Methyl tert-pentyl ether | Metsulfuron | N-(4-Chlorophenyl) -N' methylurea / Monuron | Neburon | Nicosulfuron | Norflurazon | Oryzalin | Oxamyl (Vydate) | Picloram | Propham | Propiconazol | Propoxur | Siduron | Styrene | Sulfometuron | Tebuthuron | Terbacil | Tert-butyl ethyl ether | Triazone | Tribenuron | Vinyl chloride | meta-para xylenes | o-Xylene
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled organic chemicals at this station on March 18, 2004 under the Region 6 SWAMP program. One sampling result was reported for each of the listed pollutants. All of these pollutants were below the detection level.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no applicable state or federal saltwater standards or criteria for the listed pollutants.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sampling result was reported for each of the listed pollutants from a sample or samples collected on March 18, 2004
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30507 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | 1, 3 -dichlorobenzene | 1, 4 -dichlorobenzene | 1,1,1-Trichloroethane | 1,1-Dichloroethylene (DCE)/ Vinylidene Chloride | 1,2-Dichloroethylene,-trans | 1,2-Dichloropropane | Atrazine | Benzene | Bromoform | Carbaryl | Carbon tetrachloride | Chlorobenzene (mono) | Chlorodibromomethane | Chloroform | Dichlorobromomethane | Dichlorodifluoromethane | Dichloromethane | Ethylbenzene | Methyl Tertiary-Butyl Ether (MTBE) | Tetrachloroethylene/PCE | Toluene | Trichloroethene | Trichlorofluoromethane (CFC-11) | cis-1,2-Dichloroethylene
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | These pollutants are being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. None of the samples exceeds the applicable criteria. (All pollutants were at non-detectable levels, and under Listing Policy Section 6.1.5.5, the standards are presumed to be attained.) Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy in that only one sample per pollutant was available. 3. None of the single samples for each pollutant exceeded the applicable criterion and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. However, the minimum sample number requirements of Table 3.1 were not met. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because applicable water quality standards are not being exceeded. A past cycle decision to "Do Not List" moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from another waterbody (Amargosa River-Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong wb or wb was mapped incorrectly in the past).

Line of Evidence (LOE) for Decision ID 30507, Multiple Pollutants | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46627
Pollutant: | 1, 3 -dichlorobenzene | 1, 4 -dichlorobenzene | 1,1,1-Trichloroethane | 1,1-Dichloroethylene (DCE)/ Vinylidene Chloride | 1,2-Dichloroethylene,-trans | 1,2-Dichloropropane | Atrazine | Benzene | Bromoform | Carbaryl | Carbon tetrachloride | Chlorobenzene (mono) | Chlorodibromomethane | Chloroform | Dichlorobromomethane | Dichlorodifluoromethane | Dichloromethane | Ethylbenzene | Methyl Tertiary-Butyl Ether (MTBE) | Tetrachloroethylene/PCE | Toluene | Trichloroethene | Trichlorofluoromethane (CFC-11) | cis-1,2-Dichloroethylene
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on March 17, 2004. Concentrations of the listed pollutants were all below the detection level.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | (In the following summary of criteria, when a single concentration is listed, it is the acute toxicity limit. When two concentrations are listed, the first number is the acute toxicity limit and the second is the chronic toxicity limit. U.S. Environmental Protection Agency (USEPA) national recommended saltwater aquatic life criteria for the following pollutants are as follows: atrazine, 760 ug/L/17 ug/L; carbaryl, 0.81 ug/L/0.81 ug/L; methyl tertiary butyl ether (MTBE), 53,000 ug/L/ 18,000 ug/L. The USEPA saltwater "Lowest Observed Effect Level" (LOEL) criteria are as follows: 1, 1, 1 trichloroethane, 31,200 ug/L; 1,1 dichloroethene, 224, 000 ug/L; 1, 2 dichloropropane, 10,300 ug/L; 1, 3 dichlorobenzene, 1970 ug/L/129 ug/L; 1, 4 dichlorobenzene, 1970 ug/L/ 129 ug/L; benzene, 5100 ug/L; bromodichloromethane, 12,000 ug/L/6400 ug/L; chlorobenzene 160 ug/L/129 ug/L;
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River at USGS Gage (Tecopa) was sampled.
Temporal Representation: | One sample for each of the 24 listed pollutants was collected on March 17, 2004.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30601 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Alkalinity, Carbonate as CaCO3
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This pollutant is being considered for placement on the section 303(d) list under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant.None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of one sample exceeded the objective and this does not exceed the allowable frequency listed in Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 30601, Alkalinity, Carbonate as CaCO3 | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46628
Pollutant: | Alkalinity, Carbonate as CaCO3
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Alkalinity values in two samples were 630 and 632 mg/L CaCO3.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | The USEPA's national water quality criteria recommend a minimum hardness of 20 mg/L calcium carbonate as a chronic criterion for the protection of freshwater aquatic life, unless the natural alkalinity level is lower. There are no applicable water qualitiy standards or criteria for alkalinity in inland saline waters.
Objective/Criterion Reference: | National recommended water quality criteria: 2002. EPA-822-R-02-047 Washington, D.C. USEPA
| Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30603 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Aluminum
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Three lines of evidence are available in the administrative record to assess this pollutant, but it cannot be determined if applicable water quality standards are being exceeded or not because there are no state or federal aquatic life criteria for inland saline waters. Additionally, the number of samples are limited so data are not temporally representative of the conditions in the river, which are characterized by great seasonal and annual variability in flows. The U.S. EPA's saltwater aquatic life criteria and saltwater California Toxics Rule (CTR) standards are being used to assess the SAL use for the Amargosa River. However, these criteria and standards are not appropriate for assessment of inland saline waters, which support different aquatic biota compared to marine ecosystems. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category.
Regional Board Staff Decision Recommendation: | After review of the available data and information, Lahontan Water Board staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because because there are no state or federal aquatic life criteria for inland saline waters and the data are not temporally representative of the conditions in the river, which are characterized by great seasonal and annual variability in flows.

Line of Evidence (LOE) for Decision ID 30603, Aluminum | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46630
Pollutant: | Aluminum
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. One of two samples was below the detection level and the concentration of dissolved aluminum in the other sample was an estimated value.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no applicable state or federal standards or criteria for dissolved aluminum in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 30603, Aluminum | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46631
Pollutant: | Aluminum
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Concentrations of total aluminum in two samples were 530 and 325 ug/L.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no applicable state or federal standards or criteria for total aluminum in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 30603, Aluminum | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46629
Pollutant: | Aluminum
LOE Subgroup: | Pollutant-Sediment
Matrix: | Sediment
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Chemical monitoring of sediments
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled sediment at this station on March 16, 2005 under the Region 6 SWAMP program. Results were reported as "bed sediment, smaller than 62.5 um, wet sieved, total digestion." The concentration of aluminum was 6 percent dry weight.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal standards or criteria for aluminum in sediment in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sediment sample was collected on March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30611 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Antimony
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Three lines of evidence, consisting of one or two samples each, are available in the administrative record to assess this pollutant, but it cannot be determined if applicable water quality standards are being exceeded or not because there are no state or federal aquatic life criteria for inland saline waters. Additionally, the number of samples are limited so data are not temporally representative of the conditions in the river, which are characterized by great seasonal and annual variability in flows. The U.S. EPA's saltwater aquatic life criteria and saltwater California Toxics Rule (CTR) standards are being used to assess the SAL use for the Amargosa River, and the criterion used to assess the sediment concentrations is based on levels found in marine and estuary sediments. These criteria and standards are not appropriate for assessment of inland saline waters, which support different aquatic biota compared to marine ecosystems. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category.
Regional Board Staff Decision Recommendation: | After review of the available data and information, Lahontan Water Board staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because because there are no state or federal aquatic life criteria for inland saline waters and the data are not temporally representative of the conditions in the river, which are characterized by great seasonal and annual variability in flows.

Line of Evidence (LOE) for Decision ID 30611, Antimony | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46632
Pollutant: | Antimony
LOE Subgroup: | Pollutant-Sediment
Matrix: | Sediment
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Chemical monitoring of sediments
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled sediment at this station on March 16, 2005 under the Region 6 SWAMP program. Results were reported as "bed sediment, smaller than 62.5 um, wet sieved, total digestion." The concentration of antimony was 0.7 ug/g dry weight.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal standards or criteria for antimony in sediment in inland saline waters. The Effects Range-Median for antimony in marine and estuarine sediments is 25 ug/g dry weight; see Long et al. (1995).
Objective/Criterion Reference: | Incidence of adverse biological effects within ranges of chemical concentrations in marine and estuary sediments. Environmental Management. 19, (1): 81-97
| Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sediment sample was collected on March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 30611, Antimony | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46633
Pollutant: | Antimony
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Concentrations of dissolved antimony in two samples were 0.55 and 0.59 ug/L.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no applicable state or federal standards or criteria for dissolved antimony in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 30611, Antimony | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46634
Pollutant: | Antimony
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Concentrations of total antimony in two samples were 0.4 and 0.6 ug/L.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no applicable state or federal standards or criteria for total antimony in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30656 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Barium
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. There are no applicable water quality standards or criteria for barium in the sediment of inland saline waters. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the single sample cannot be assessed using Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded because there are no applicable water quality standards or criteria developed for inland saline waters.

Line of Evidence (LOE) for Decision ID 30656, Barium | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46638
Pollutant: | Barium
LOE Subgroup: | Pollutant-Sediment
Matrix: | Sediment
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Chemical monitoring of sediments
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled sediment at this station on March 18 2004 under the Region 6 SWAMP program. Results were reported as "bed sediment, smaller than 62.5 um, wet sieved, total digestion." The concentration of barium was 790 ug/g dry weight.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal standards or criteria for barium in sediment in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sediment sample was collected on March 18, 2004.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30612 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Beryllium
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Three lines of evidence, consisting of one or two samples each, are available in the administrative record to assess this pollutant. However, it is difficult to assess whether applicable water quality standards are being exceeded or met because there are no state or federal aquatic life criteria for inland saline waters. Additionally, the number of samples are limited so data are not temporally representative of the conditions in the river, which are characterized by great seasonal and annual variability in flows. The U.S. EPA's saltwater aquatic life criteria and saltwater California Toxics Rule (CTR) standards are being used to assess the SAL benefical use for the Amargosa River, and the criterion used to assess the sediment concentrations is based on levels found in marine and estuary sediments. These criteria and standards are not appropriate for assessment of inland saline waters, which support different aquatic biota compared to marine ecosystems. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category.
Regional Board Staff Decision Recommendation: | After review of the available data and information, Lahontan Water Board staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because because there are no state or federal aquatic life criteria for inland saline waters and the data are not temporally representative of the conditions in the river, which are characterized by great seasonal and annual variability in flows.

Line of Evidence (LOE) for Decision ID 30612, Beryllium | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46640
Pollutant: | Beryllium
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Concentrations of total beryllium in two samples were both below the detection level.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no applicable state or federal saltwater aquatic life standards or criteria for total beryllium in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 30612, Beryllium | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46641
Pollutant: | Beryllium
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Concentrations of dissolved beryllium in two samples were both below the detection level.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no applicable state or federal saltwater aquatic life standards or criteria for dissolved beryllium in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 30612, Beryllium | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46639
Pollutant: | Beryllium
LOE Subgroup: | Pollutant-Sediment
Matrix: | Sediment
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Chemical monitoring of sediments
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled sediment at this station on March 16. 2005 under the Region 6 SWAMP program. Results were reported as "bed sediment, smaller than 62.5 um, wet sieved, total digestion." The concentration of beryllium was 2 ug/g dry weight.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal standards or criteria for beryllium in sediment in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sediment sample was collected on March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30657 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Bicarbonate
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. There are no applicable state or federal saltwater aquatic life standards or criteria for bicarbonate in inland saline waters. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The sediment data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the data cannot be assessed using Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because there are no applicable water quality standards or criteria.

Line of Evidence (LOE) for Decision ID 30657, Bicarbonate | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46642
Pollutant: | Bicarbonate
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Two samples had bicarbonate concentrations of 722 and 673 mg/L.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no applicable state or federal saltwater aquatic life standards or criteria for bicarbonate in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30658 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Bismuth
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence, consisting of a single sediment sample, is available in the administrative record to assess this pollutant. There are no applicable water quality standards or criteria for bismuth in the sediment of inland saline waters. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the single sample cannot be assessed using Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because there are no applicable water quality standards or criteria and the minimum sample number requirements of the Listing Policy are not met.

Line of Evidence (LOE) for Decision ID 30658, Bismuth | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46643
Pollutant: | Bismuth
LOE Subgroup: | Pollutant-Sediment
Matrix: | Sediment
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Chemical monitoring of sediments
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled sediment at this station on March 16, 2005 under the Region 6 SWAMP program. Results were reported as "bed sediment, smaller than 62.5 um, wet sieved, total digestion." The concentration of bismuth was below the detection level.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal standards or criteria for bismuth in sediment in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sediment sample was collected on March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30659 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Boron
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. There are no applicable water quality standards or criteria for this pollutant in inland saline waters. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used (only one sample per year) do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the minimum sample number requirements of Table 3.1 of the Listing Policy are not met. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because there are no applicable water quality standards or criteria and the number of samples do not satisfy the minimum sample size in the listing policy.

Line of Evidence (LOE) for Decision ID 30659, Boron | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46644
Pollutant: | Boron
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Concentrations of dissolved boron in two samples were 9540 and 8930 ug/L.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no applicable state or federal aquatic life standards or criteria for boron in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30613 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Cadmium
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Three lines of evidence, consisting of one or two samples each, are available in the administrative record to assess this pollutant. However, it is difficult to assess whether applicable water quality standards are being exceeded or met because the number of samples are limited and there are no state or federal aquatic life criteria for inland saline waters or for inland saline sediment. The U.S. EPA's saltwater aquatic life criteria and saltwater California Toxics Rule (CTR) standards are being used to assess the SAL use for the Amargosa River, and the criterion used to assess the sediment concentrations is based on levels found in marine and estuary sediments. These criteria and standards are not appropriate for assessment of inland saline waters, which support different aquatic biota compared to marine ecosystems. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category.
Regional Board Staff Decision Recommendation: | After review of the available data and information, Lahontan Water Board staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because because there are no state or federal aquatic life criteria for inland saline waters and the data are not temporally representative of the conditions in the river, which are characterized by great seasonal and annual variability in flows.

Line of Evidence (LOE) for Decision ID 30613, Cadmium | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46646
Pollutant: | Cadmium
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Concentrations of dissolved cadmium in two samples were 0.13 and 0.14 ug/L.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | The California Toxics Rule's saltwater aquatic life standards for cadmium include an acute toxicity limit of 42 ug/L and a chronic toxicity limit of 9.3 ug/L.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 30613, Cadmium | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46647
Pollutant: | Cadmium
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Concentrations of total cadmium in two samples were 0.12 and 0.17 ug/L.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no applicable state or federal saltwater aquatic life standards or criteria for total cadmium in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 30613, Cadmium | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46645
Pollutant: | Cadmium
LOE Subgroup: | Pollutant-Sediment
Matrix: | Sediment
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Chemical monitoring of sediments
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled sediment at this station on March 16, 2005 under the Region 6 SWAMP program. Results were reported as "bed sediment, smaller than 62.5 um, wet sieved, total digestion." The concentration of cadmium was 0.1 ug/g dry weight.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal standards or criteria for cadmium in sediment in inland saline waters. The Probable Effects Level for cadmium in marine and estuarine sediments is 4.21 ug/g dry weight; see MacDonald et al. (1996).
Objective/Criterion Reference: | Development and evaluation of sediment quality guidelines for Florida coastal waters. Ecotoxicology 5: 253-278
| Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sediment sample was collected on March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30660 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Caffeine
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. There are no applicable water quality standards or criteria. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The single sample does not satisfy the data quantity requirements of section 6.1.5 of the Policy. The single sample is not temporally representative of the conditions in the river, which are characterized by great seasonal and annual variability in flows. 3. There are no applicable water quality standards or criteria and the data cannot be assessed using Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because there are no applicable water quality standards or criteria and the number of samples to not satisfy the minimum sample size in the listing policy.

Line of Evidence (LOE) for Decision ID 30660, Caffeine | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46648
Pollutant: | Caffeine
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sample this station on March 16 2005 under the Region 6 SWAMP program. The concentration of caffeine in one sample was below the detection level.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal standards or criteria for caffeine in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sediment sample was collected on March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30614 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Calcium
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Three lines of evidence, consisting of one or two samples each, are available in the administrative record to assess this pollutant. However, it is difficult to assess whether applicable water quality standards are being exceeded or met because the number of samples are limited and there are no state or federal aquatic life criteria for inland saline waters or for inland saline sediment. The U.S. EPA's saltwater aquatic life criteria and saltwater California Toxics Rule (CTR) standards are being used to assess the SAL use for the Amargosa River, and the criterion used to assess the sediment concentrations is based on levels found in marine and estuary sediments. These criteria and standards are not appropriate for assessment of inland saline waters, which support different aquatic biota compared to marine ecosystems. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because (1) samples are limited and (2) it cannot be determined if applicable water quality standards are not being exceeded because there are no state or federal aquatic life criteria for inland saline waters.

Line of Evidence (LOE) for Decision ID 30614, Calcium | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46649
Pollutant: | Calcium
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Two samples had dissolved calcium concentrations of 37.5 and 62.1 mg/L.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no applicable state or federal standards or criteria for dissolved calcium in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 30614, Calcium | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46651
Pollutant: | Calcium
LOE Subgroup: | Pollutant-Sediment
Matrix: | Sediment
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Chemical monitoring of sediments
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled sediment at this station on March 16, 2005 under the Region 6 SWAMP program. Results were reported as "bed sediment, smaller than 62.5 um, wet sieved, total digestion." The concentration of calcium was 3.5 percent dry weight.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal standards or criteria for calcium in sediment in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sediment sample was collected on March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 30614, Calcium | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46650
Pollutant: | Calcium
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Two samples had total calcium concentrations of 47.7 and 65.1 mg/L.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no applicable state or federal standards or criteria for total calcium in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30751 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Carbon (organic + inorganic)
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. There are no applicable water quality standards or criteria for inorganic plus organic carbon. It is difficult to assess whether applicable water quality standards are being exceeded or met because the number of samples are limited and there are no state or federal aquatic life criteria for inland saline waters or for inland saline sediment. The criterion used to assess the sediment concentrations is based on levels found in marine and estuary sediments. These criteria are not appropriate for assessment of inland saline waters, which support different aquatic biota compared to marine ecosystems. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the data cannot be assessed using Table 3.2 of the Listing Policy. The minimum sample number requirements of Table 3.2 are not met. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. RB Decision
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because (1) the minimum sample number requirements of the Listing Policy are not met and (2) it cannot be determined if applicable water quality standards are being exceeded because there are no state or federal aquatic life criteria for inland saline waters or inland saline sediment.

Line of Evidence (LOE) for Decision ID 30751, Carbon (organic + inorganic) | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46652
Pollutant: | Carbon (organic + inorganic)
LOE Subgroup: | Pollutant-Sediment
Matrix: | Sediment
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Chemical monitoring of sediments
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled sediment at this station on March 16, 2005 under the Region 6 SWAMP program. Results were reported as "bed sediment, smaller than 62.5 um, wet sieved, total digestion." The concentration of carbon (inorganic + organic) was 1 percent dry weight.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal standards or criteria for carbon in sediment in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sediment sample was collected on March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30752 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Carbon (organic)
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. There are no applicable water quality standards or criteria for organic carbon. It is difficult to assess whether applicable water quality standards are being exceeded or met because the number of samples are limited and there are no state or federal aquatic life criteria for inland saline waters or for inland saline sediment. The criterion used to assess the sediment concentrations is based on levels found in marine and estuary sediments. These criteria and standards are not appropriate for assessment of inland saline waters and sediment, which support different aquatic biota compared to marine ecosystems. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the data cannot be assessed using Table 3.2 of the Listing Policy. The minimum sample number requirements of Table 3.2 are not met. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because (1) the minimum sample number requirements of the Listing Policy are not met and (2) it cannot be determined if applicable water quality standards are being exceeded because there are no state or federal aquatic life criteria for inland saline waters or inland saline sediment.

Line of Evidence (LOE) for Decision ID 30752, Carbon (organic) | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46654
Pollutant: | Carbon (organic)
LOE Subgroup: | Pollutant-Sediment
Matrix: | Sediment
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Chemical monitoring of sediments
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled sediment at this station on March 16, 2005 under the Region 6 SWAMP program. Results were reported as "bed sediment, smaller than 62.5 um, wet sieved, total digestion." The concentration of carbon (organic) was 0.09 percent dry weight.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal standards or criteria for organic carbon in sediment in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sediment sample was collected on March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30762 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Carbonate
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. One line of evidence, consisting of two samples, is available in the administrative record to assess this pollutant. There are no applicable water quality standards or criteria for carbonate in inland saline waters. It is difficult to assess whether applicable water quality standards are being exceeded or met because the number of samples are limited and there are no state or federal aquatic life criteria for inland saline waters. The U.S. EPA's saltwater aquatic life criteria and saltwater California Toxics Rule (CTR) standards are being used to assess the SAL use for the Amargosa River, are based on levels found in marine and estuary waters. These criteria and standards are not appropriate for assessment of inland saline waters, which support different aquatic biota compared to marine ecosystems. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the data cannot be assessed using Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because there are no applicable water quality standards or criteria, and the minimum sample number requirements of the Listing Policy are not met.

Line of Evidence (LOE) for Decision ID 30762, Carbonate | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46655
Pollutant: | Carbonate
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Two samples had carbonate concentrations of 23 and 48 mg/L.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no applicable state or federal saltwater aquatic life standards or criteria for carbonate in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30763 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Cerium
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. There are no applicable water quality standards or criteria.It is difficult to assess whether applicable water quality standards are being exceeded or met because the number of samples are limited and there are no state or federal aquatic life criteria for inland saline sediment. The criterion used to assess the sediment concentrations is based on levels found in marine and estuary sediments. These criteria are not appropriate to assess the SAL use for the Amargosa River, which support different aquatic biota compared to marine ecosystems. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The single sample does not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the data cannot be assessed using Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because (1) the minimum sample number requirements of the Listing Policy are not met and (2) it cannot be determined if applicable water quality standards are being exceeded because there are no state or federal aquatic life criteria for inland saline waters or inland saline sediment.

Line of Evidence (LOE) for Decision ID 30763, Cerium | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46656
Pollutant: | Cerium
LOE Subgroup: | Pollutant-Sediment
Matrix: | Sediment
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Chemical monitoring of sediments
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled sediment at this station on March 16, 2005 under the Region 6 SWAMP program. Results were reported as "bed sediment, smaller than 62.5 um, wet sieved, total digestion." The concentration of cerium was 76 ug/g dry weight.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal standards or criteria for cerium in sediment in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sediment sample was collected on March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30764 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Chloride
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. One line of evidence, consisting of two samples, is available in the administrative record to assess this pollutant. There are no applicable water quality standards or criteria for chloride in inland saline waters. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the data cannot be assessed using Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because there are no applicable water quality standards or criteria, and the minimum sample number requirements of the Listing Policy are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because there are no applicable water quality standards or criteria, and the minimum sample number requirements of the Listing Policy are not met.

Line of Evidence (LOE) for Decision ID 30764, Chloride | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46657
Pollutant: | Chloride
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Two samples had dissolved chloride concentrations of 427 and 337 mg/L.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no applicable state or federal saltwater aquatic life standards or criteria for chloride in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30615 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Chromium (total)
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Three lines of evidence, consisting of one or two samples each, are available in the administrative record to assess this pollutant. However, it is difficult to assess whether applicable water quality standards are being exceeded or met because the number of samples are limited and there are no state or federal aquatic life criteria for inland saline waters or for inland saline sediment. The U.S. EPA's saltwater aquatic life criteria and saltwater California Toxics Rule (CTR) standards are being used to assess the SAL use for the Amargosa River, and the criterion used to assess the sediment concentrations is based on levels found in marine and estuary sediments. These criteria and standards are not appropriate for assessment of inland saline waters, which support different aquatic biota compared to marine ecosystems. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because (1) samples are limited and (2) it cannot be determined if applicable water quality standards are not being exceeded because there are no state or federal aquatic life criteria for inland saline waters.

Line of Evidence (LOE) for Decision ID 30615, Chromium (total) | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46660
Pollutant: | Chromium (total)
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. One of two samples for dissolved chromium was below the detection level and the other was an estimated value.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | The California Toxics Rule's saltwater aquatic life standards for chromium include an acute toxicity limit of 1100 ug/L and a chronic toxicity limit of 50 ug/L.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 30615, Chromium (total) | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46659
Pollutant: | Chromium (total)
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Concentrations of total chromium in both of two samples were estimated values.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no applicable state or federal saltwater aquatic life standards or criteria for total chromium in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 30615, Chromium (total) | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46658
Pollutant: | Chromium (total)
LOE Subgroup: | Pollutant-Sediment
Matrix: | Sediment
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Chemical monitoring of sediments
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled sediment at this station on March 16, 2005 under the Region 6 SWAMP program. Results were reported as "bed sediment, smaller than 62.5 um, wet sieved, total digestion." The concentration of chromium was 21 ug/g dry weight. (The SWAMP data do not distinguish between trivalent and hexavalent chromium.)
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal standards or criteria for arsenic in sediment in inland saline waters. The Effects Range-Median for chromium in marine and estuarine sediments is 370 ug/g dry weight; see Long et al. (1995).
Objective/Criterion Reference: | Incidence of adverse biological effects within ranges of chemical concentrations in marine and estuary sediments. Environmental Management. 19, (1): 81-97
| Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sediment sample was collected on March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30616 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Cobalt
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Three lines of evidence, consisting of one or two samples each, are available in the administrative record to assess this pollutant. However, it is difficult to assess whether applicable water quality standards are being exceeded or met because the number of samples are limited and there are no state or federal aquatic life criteria for inland saline waters or for inland saline sediment. The U.S. EPA's saltwater aquatic life criteria and saltwater California Toxics Rule (CTR) standards are being used to assess the SAL use for the Amargosa River, and the criterion used to assess the sediment concentrations is based on levels found in marine and estuary sediments. These criteria and standards are not appropriate for assessment of inland saline waters, which support different aquatic biota compared to marine ecosystems. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because (1) samples are limited and (2) it cannot be determined if applicable water quality standards are not being exceeded because there are no state or federal aquatic life criteria for inland saline waters.

Line of Evidence (LOE) for Decision ID 30616, Cobalt | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46662
Pollutant: | Cobalt
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Concentrations of total cobalt in two samples were 0.56 and 0.8 ug/L.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no applicable state or federal saltwater aquatic life standards or criteria for total cobalt in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 30616, Cobalt | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46663
Pollutant: | Cobalt
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Concentrations of dissolved cobalt in two samples were 0.24 and 0.37 ug/L.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no applicable state or federal saltwater aquatic life standards or criteria for dissolved cobalt in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 30616, Cobalt | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46661
Pollutant: | Cobalt
LOE Subgroup: | Pollutant-Sediment
Matrix: | Sediment
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Chemical monitoring of sediments
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled sediment at this station on March 16, 2005 under the Region 6 SWAMP program. Results were reported as "bed sediment, smaller than 62.5 um, wet sieved, total digestion." The concentration of cobalt was 6 ug/g dry weight.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal standards or criteria for cobalt in sediment in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sediment sample was collected on March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30617 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Copper
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed in wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Three lines of evidence, including total and dissolved copper in water and copper in sediment, are available in the administrative record to assess this pollutant. Two of the dissolved copper samples exceed the California Toxics Rule chronic toxicity standard. This standard is based on toxicity tests for marine/estuarine organisms and is not appropriate for inland saline waters, which support different aquatic biota compared to marine ecosystems. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. Two samples, one collected in March 2006 and another collected in March 2007, are not temporally representative of the great annual and seasonal variability of flows in the Amargosa River. 3. Two out of two dissolved copper water samples exceeded the California Toxics Rule standard and this exceeds the allowable frequency listed in Table 3.1 of the Listing Policy. However, as explained above, the standard is inappropriate for inland saline waters. The standard was developed using marine and estuarine organisms, and inland saline waters support different aquatic biota. Inland saline water organisms are adapted to greater extremes of and fluctuations in environmental conditions than marine organisms. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because, although the California Toxics Rule standards are being exceeded, the standards, which are based on protection of marine/estuarine organisms are inappropriate for evaluation of inland saline waters. Additionally, the data do not temporally capture the great seasonal and annual variability in flows that characterize this segment of the Amargosa River.

Line of Evidence (LOE) for Decision ID 30617, Copper | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46665
Pollutant: | Copper
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 2
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Concentrations of dissolved copper in two samples were 3.3 and 3.2 ug/L.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | The California Toxics Rule's saltwater aquatic life standards for dissolved copper include an acute toxicity limit of 4.8 ug/L and a chronic toxicity limit of 3.1 ug/L.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 30617, Copper | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46666
Pollutant: | Copper
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Concentrations of total copper in two samples were 6.3 and 14.8 ug/L.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no applicable state or federal saltwater aquatic life standards or criteria for total copper in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 30617, Copper | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46664
Pollutant: | Copper
LOE Subgroup: | Pollutant-Sediment
Matrix: | Sediment
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Chemical monitoring of sediments
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled sediment at this station on March 16, 2005 under the Region 6 SWAMP program. Results were reported as "bed sediment, smaller than 62.5 um, wet sieved, total digestion." The concentration of copper was 10 ug/g dry weight.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal standards or criteria for copper in sediment in inland saline waters. The Effects Range-Median for copper in marine and estuarine sediments is 270 ug/g dry weight; see Long et al. (1995).
Objective/Criterion Reference: | Incidence of adverse biological effects within ranges of chemical concentrations in marine and estuary sediments. Environmental Management. 19, (1): 81-97
| Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sediment sample was collected on March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30749 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Deuterium/Protium ratio
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. There are no applicable water quality standards or criteria for this parameter.. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the data cannot be assessed using Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded because sampling is limited and there are no applicable water quality standards or criteria.

Line of Evidence (LOE) for Decision ID 30749, Deuterium/Protium ratio | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46667
Pollutant: | Deuterium/Protium ratio
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. The deuterium/protium ratios in two samples were -90.7 and -90.1 per mL.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal saltwater aquatic life standards or criteria for deuterium/protium ratio in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30648 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Dissolved oxygen saturation
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This pollutant is being considered for placement on the section 303(d) list under section 3.2 of the Listing Policy. Under section 3.2, one line of evidence is necessary to assess listing status. One line of evidence are available in the administrative record to assess this pollutant. One of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used so not satisfy the data quantity requirements of section 6.1.5 of the Policy. The number of samples are limited so data are not temporally representative of the conditions in the river, which are characterized by great seasonal and annual variability in flows. 3. One of two samples exceeded the objective and this sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 26 samples is needed for application of table 3.2. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 30648, Dissolved oxygen saturation | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46749
Pollutant: | Dissolved oxygen saturation
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 1
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Two sample had dissolved oxygen saturation values of 106 and 75 percent.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | .The Lahontan Basin Plan's water quality objective states that percent saturation shall not be depressed by more than 10 percent and minimum dissolved oxygen concentration shall not be less than 80 percent saturation.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30750 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Europium
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. However, it is difficult to assess whether applicable water quality standards are being exceeded or met because the number of samples are limited and there are no state or federal aquatic life criteria for inland saline sediment. The criterion used to assess the sediment concentrations is based on levels found in marine and estuary sediments. These criteria and standards are not appropriate for assessment of inland saline waters, which support different aquatic biota compared to marine ecosystems. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no state or federal standards or criteria for europium in sediment in inland saline waters. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because (1) samples are limited and (2) it cannot be determined if applicable water quality standards are not being exceeded because there are no state or federal aquatic life criteria for inland saline waters or sediment.

Line of Evidence (LOE) for Decision ID 30750, Europium | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46668
Pollutant: | Europium
LOE Subgroup: | Pollutant-Sediment
Matrix: | Sediment
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Chemical monitoring of sediments
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled sediment at this station on March 16, 2005 under the Region 6 SWAMP program. Results were reported as "bed sediment, smaller than 62.5 um, wet sieved, total digestion." The concentration of europium was 1 ug/g dry weight.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal standards or criteria for europium in sediment in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sediment sample was collected on March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30767 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Fecal Coliform
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used does not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. None of one sample exceeded the objective and this does not exceed the allowable frequency listed in Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 30767, Fecal Coliform | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46753
Pollutant: | Fecal Coliform
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Water column surveys (e.g. fecal coliform)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled sediment at this station on March 18 2004 under the Region 6 SWAMP program. The fecal coliform count in one sample was an estimated value.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | The Lahontan Basin Plan's objective for coliform bacteria states: "Waters shall not contain concentrations of coliform organisms attributable to anthropogenic sources, including human and livestock wastes. The fecal coliform concentration during any 30-day period shall not exceed a log mean of 20/100 ml, nor shall more than 10 percent of all samples collected during any 30-day period exceed 40/100 ml. The log mean shall ideally be based on a minimum of not less than five samples collected as evenly spaced as practicable during any 30-day period. However, a log mean concentration exceeding 20/100 ml for any 30-day period shall indicate violation of this objective even if fewer than five samples were collected."
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sample was collected on March 18, 2004.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30768 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Fluoride
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). The U.S. EPA's saltwater aquatic life criteria and saltwater California Toxics Rule (CTR) standards are being used to assess the SAL use for the Amargosa River. However, these criteria and standards are not appropriate for assessment of inland saline waters, which support different aquatic biota compared to marine ecosystems. This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One lines of evidence is available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable state or federal salt water aquatic life standards for inland saline waters. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because (1) samples are limited and (2) it cannot be determined if applicable water quality standards are not being exceeded because there are no state or federal aquatic life criteria for inland saline waters.

Line of Evidence (LOE) for Decision ID 30768, Fluoride | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46669
Pollutant: | Fluoride
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Two samples had dissolved fluoride concentrations of 4.5 and 4.0 mg/L.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no applicable state or federal saltwater aquatic life standards or criteria for fluoride in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30770 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Gallium
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no state or federal standards or criteria for gallium in sediment in inland saline waters. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because (1) the minimum sample number requirements of the Listing Policy are not met and (2) it cannot be determined if applicable water quality standards are being exceeded because there are no state or federal aquatic life criteria for inland saline waters or inland saline sediment.

Line of Evidence (LOE) for Decision ID 30770, Gallium | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46670
Pollutant: | Gallium
LOE Subgroup: | Pollutant-Sediment
Matrix: | Sediment
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Chemical monitoring of sediments
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled sediment at this station on March 16, 2005 under the Region 6 SWAMP program. Results were reported as "bed sediment, smaller than 62.5 um, wet sieved, total digestion." The concentration of gallium was 13 ug/g dry weight.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal standards or criteria for gallium in sediment in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sediment sample was collected on March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30771 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Gold
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant.There are no state or federal standards or criteria for gold in sediment in inland saline waters. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no state or federal standards or criteria for gold in sediment in inland saline waters. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because (1) the minimum sample number requirements of the Listing Policy are not met and (2) it cannot be determined if applicable water quality standards are being exceeded because there are no state or federal aquatic life criteria for inland saline waters or inland saline sediment.

Line of Evidence (LOE) for Decision ID 30771, Gold | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46671
Pollutant: | Gold
LOE Subgroup: | Pollutant-Sediment
Matrix: | Sediment
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Chemical monitoring of sediments
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled sediment at this station on March 16, 2005 under the Region 6 SWAMP program. Results were reported as "bed sediment, smaller than 62.5 um, wet sieved, total digestion." The concentration of gold was below the detection level.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal standards or criteria for gold in sediment in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sediment sample was collected on March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30772 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Gross Alpha Radioactivity
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. The number of samples are limited so data are not temporally representative of the conditions in the river, which are characterized by great seasonal and annual variability in flows. 3. There are no state or federal saltwater aquatic life standards or criteria specifically for gross alpha radioactivity in inland saline waters. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. There are no state or federal saltwater aquatic life standards or criteria specifically for gross alpha radioactivity in inland saline waters. The Lahontan Basin Plan's narrative objective for radioactivity provdes that: "Radionuclides shall not be present in concentrations which are deleterious to human, plant, animal, or aquatic life nor which result in the accumulation of radionuclides in the food web to an estent which presents a hazard to human, plant, animal or aquatic life." The objective also incorporates California Maximum Contaminant Levels for waters designated for the MUN use. MCLs do not apply to the Amargosa River.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because (1) the minimum sample number requirements of the Listing Policy are not met and (2) it cannot be determined if applicable water quality standards are being exceeded because there are no state or federal aquatic life criteria for inland saline waters or inland saline sediment.

Line of Evidence (LOE) for Decision ID 30772, Gross Alpha Radioactivity | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46672
Pollutant: | Gross Alpha Radioactivity
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Two samples had gross alpha radioactivity levels of 13 and 30 pCi/L..
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal saltwater aquatic life standards or criteria specifically for gross alpha radioactivity in inland saline waters. The Lahontan Basin Plan's narrative objective for radioactivity provdes that: "Radionuclides shall not be present in concentrations which are deleterious to human, plant, animal, or aquatic life nor which result in the accumulation of radionuclides in the food web to an estent which presents a hazard to human, plant, animal or aquatic life." The objective also incorporates California Maximum Contaminant Levels for waters designated for the MUN use. MCLs do not apply to the Amargosa River.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30773 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Gross Beta Radioactivity
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. There are no state or federal saltwater aquatic life standards or criteria specifically for gross beta radioactivity in inland saline waters. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no state or federal saltwater aquatic life standards or criteria specifically for gross beta radioactivity in inland saline waters. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. There are no state or federal saltwater aquatic life standards or criteria specifically for gross beta radioactivity in inland saline waters. The Lahontan Basin Plan's narrative objective for radioactivity provdes that: "Radionuclides shall not be present in concentrations which are deleterious to human, plant, animal, or aquatic life nor which result in the accumulation of radionuclides in the food web to an estent which presents a hazard to human, plant, animal or aquatic life." The objective also incorporates California Maximum Contaminant Levels for waters designated for the MUN use. MCLs do not apply to the Amargosa River.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because (1) the minimum sample number requirements of the Listing Policy are not met and (2) it cannot be determined if applicable water quality standards are being exceeded because there are no state or federal aquatic life criteria for inland saline waters or inland saline sediment.

Line of Evidence (LOE) for Decision ID 30773, Gross Beta Radioactivity | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46673
Pollutant: | Gross Beta Radioactivity
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Two samples had gross beta radioactivity levels of 45 and 64 pCi/L..
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal saltwater aquatic life standards or criteria specifically for gross beta radioactivity in inland saline waters. The Lahontan Basin Plan's narrative objective for radioactivity provdes that: "Radionuclides shall not be present in concentrations which are deleterious to human, plant, animal, or aquatic life nor which result in the accumulation of radionuclides in the food web to an estent which presents a hazard to human, plant, animal or aquatic life." The objective also incorporates California Maximum Contaminant Levels for waters designated for the MUN use. MCLs do not apply to the Amargosa River.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30774 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Hardness
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. There are no state or federal saltwater aquatic life standards or criteria for hardness in inland saline waters. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. The number of samples are limited so data are not temporally representative of the conditions in the river, which are characterized by great seasonal and annual variability in flows. 3. There are no state or federal saltwater aquatic life standards or criteria for hardness in inland saline waters. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. There are no state or federal saltwater aquatic life standards or criteria for hardness in inland saline waters. Hardness is monitored for purposes such as determination of the applicable criteria and standards for metals whose toxicity is hardness-dependent. The U.S. Environmental Protection Agency's 1986 "Gold Book" includes generally accepted categories of hardness. Calcium and magnesium are the major ions contributing to hardness, and hardness is generally expressed as calcium carbonate. Water with a hardness equivalent to 0-75 mg equivalent CaCO3/L is considered "soft."
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because (1) the minimum sample number requirements of the Listing Policy are not met and (2) it cannot be determined if applicable water quality standards are being exceeded because there are no state or federal aquatic life criteria for inland saline waters or inland saline sediment.

Line of Evidence (LOE) for Decision ID 30774, Hardness | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46674
Pollutant: | Hardness
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Two samples had hardness values of 240 and 380 mg/L CaCO3.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal saltwater aquatic life standards or criteria for hardness in inland saline waters. Hardness is monitored for purposes such as determination of the applicable criteria and standards for metals whose toxicity is hardness-dependent. The U.S. Environmental Protection Agency's 1986 "Gold Book" includes generally accepted categories of hardness. Calcium and magnesium are the major ions contributing to hardness, and hardness is generally expressed as calcium carbonate. Water with a hardness equivalent to 0-75 mg equivalent CaCO3/L is considered "soft."
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30775 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Holmium
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. There are no state or federal standards or criteria for holmium in sediment in inland saline waters. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfy data quantity requirements of section 6.1.5 of the Policy. 3. There are no state or federal standards or criteria for holmium in sediment in inland saline waters. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because (1) the minimum sample number requirements of the Listing Policy are not met and (2) it cannot be determined if applicable water quality standards are being exceeded because there are no state or federal aquatic life criteria for inland saline waters or inland saline sediment.

Line of Evidence (LOE) for Decision ID 30775, Holmium | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46675
Pollutant: | Holmium
LOE Subgroup: | Pollutant-Sediment
Matrix: | Sediment
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Chemical monitoring of sediments
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled sediment at this station on March 16, 2005 under the Region 6 SWAMP program. Results were reported as "bed sediment, smaller than 62.5 um, wet sieved, total digestion." The concentration of holmium was below the detection level.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal standards or criteria for holmium in sediment in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sediment sample was collected on March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30618 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Iron
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Three lines of evidence, consisting of one or two samples each, are available in the administrative record to assess this pollutant. However, it is difficult to assess whether applicable water quality standards are being exceeded or met because the number of samples are limited and there are no state or federal aquatic life criteria for inland saline waters or for inland saline sediment. The U.S. EPA's saltwater aquatic life criteria and saltwater California Toxics Rule (CTR) standards are being used to assess the SAL use for the Amargosa River, and the criterion used to assess the sediment concentrations is based on levels found in marine and estuary sediments. These criteria and standards are not appropriate for assessment of inland saline waters, which support different aquatic biota compared to marine ecosystems. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. The number of samples are limited so data are not temporally representative of the conditions in the river, which are characterized by great seasonal and annual variability in flows. 3. There are no state or federal saltwater aquatic life standards or criteria for iron in inland saline waters or sediment. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because (1) samples are limited and (2) it cannot be determined if applicable water quality standards are not being exceeded because there are no state or federal aquatic life criteria for inland saline waters.

Line of Evidence (LOE) for Decision ID 30618, Iron | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46676
Pollutant: | Iron
LOE Subgroup: | Pollutant-Sediment
Matrix: | Sediment
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Chemical monitoring of sediments
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled sediment at this station on March 16, 2005 under the Region 6 SWAMP program. Results were reported as "bed sediment, smaller than 62.5 um, wet sieved, total digestion." The concentration of iron was 1.7 percent dry weight.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal standards or criteria for iron in sediment in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sediment sample was collected on March 16, 2004.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 30618, Iron | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46678
Pollutant: | Iron
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. One of two samples for total iron was an estimated value and the other had a concentration of 30 ug/L.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no applicable state or federal saltwater aquatic life standards or criteria for total iron in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 30618, Iron | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46677
Pollutant: | Iron
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. One of two samples for dissolved iron was an estimated value and the other had a concentration of 30 ug/L.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no applicable state or federal saltwater aquatic life standards or criteria for dissolved iron in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30776 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Lanthanum
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. There are no state or federal standards or criteria for lanthanum in sediment in inland saline waters. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no state or federal standards or criteria for lanthanum in sediment in inland saline waters. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because (1) the minimum sample number requirements of the Listing Policy are not met and (2) it cannot be determined if applicable water quality standards are being exceeded because there are no state or federal aquatic life criteria for inland saline waters or inland saline sediment.

Line of Evidence (LOE) for Decision ID 30776, Lanthanum | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46680
Pollutant: | Lanthanum
LOE Subgroup: | Pollutant-Sediment
Matrix: | Sediment
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Chemical monitoring of sediments
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled sediment at this station on March 16, 2005 under the Region 6 SWAMP program. Results were reported as "bed sediment, smaller than 62.5 um, wet sieved, total digestion." The concentration of lanthanum was 40 ug/g dry weight.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal standards or criteria for lanthanum in sediment in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sediment sample was collected on March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30619 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Lead
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Three lines of evidence, consisting of one or two samples each, are available in the administrative record to assess this pollutant. However, it is difficult to assess whether applicable water quality standards are being exceeded or met because the number of samples are limited and there are no state or federal aquatic life criteria for inland saline waters or for inland saline sediment. The U.S. EPA's saltwater aquatic life criteria and saltwater California Toxics Rule (CTR) standards are being used to assess the SAL use for the Amargosa River, and the criterion used to assess the sediment concentrations is based on levels found in marine and estuary sediments. These criteria and standards are not appropriate for assessment of inland saline waters, which support different aquatic biota compared to marine ecosystems. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because (1) samples are limited and (2) it cannot be determined if applicable water quality standards are not being exceeded because there are no state or federal aquatic life criteria for inland saline waters.

Line of Evidence (LOE) for Decision ID 30619, Lead | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46681
Pollutant: | Lead
LOE Subgroup: | Pollutant-Sediment
Matrix: | Sediment
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Chemical monitoring of sediments
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled sediment at this station on March 16, 2005 under the Region 6 SWAMP program. Results were reported as "bed sediment, smaller than 62.5 um, wet sieved, total digestion." The concentration of lead was 28 ug/g dry weight.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal standards or criteria for lead in sediment in inland saline waters. The Probable Effects Level for lead in marine and estuarine sediments is 112.18 ug/g dry weight; see MacDonald et al. (1996).
Objective/Criterion Reference: | Development and evaluation of sediment quality guidelines for Florida coastal waters. Ecotoxicology 5: 253-278
| Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sediment sample was collected on March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 30619, Lead | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46682
Pollutant: | Lead
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Concentrations of dissolved lead in two samples were 0.21 and 0.22 ug/L.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | The California Toxics Rule's saltwater aquatic life standards for dissolved lead include an acute toxicity limit of 210 ug/L and a chronic toxicity limit of 8.1 ug/L.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 30619, Lead | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46683
Pollutant: | Lead
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Concentrations of total lead in two samples were 0.61 and 0.6 ug/L.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no applicable state or federal saltwater aquatic life standards or criteria for total lead in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30777 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Lithium
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. There are no state or federal standards or criteria for lithium in sediment in inland saline waters. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no state or federal standards or criteria for lithium in sediment in inland saline waters. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because (1) the minimum sample number requirements of the Listing Policy are not met and (2) it cannot be determined if applicable water quality standards are being exceeded because there are no state or federal aquatic life criteria for inland saline waters or inland saline sediment.

Line of Evidence (LOE) for Decision ID 30777, Lithium | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46684
Pollutant: | Lithium
LOE Subgroup: | Pollutant-Sediment
Matrix: | Sediment
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Chemical monitoring of sediments
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled sediment at this station on March 16, 2005 under the Region 6 SWAMP program. Results were reported as "bed sediment, smaller than 62.5 um, wet sieved, total digestion." The concentration of lithium was 33 ug/g dry weight.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal standards or criteria for lithium in sediment in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sediment sample was collected on March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30778 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Magnesium
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Three lines of evidence are available in the administrative record to assess this pollutant. Samples include water and sediment samples. There are no applicable state or federal standards or criteria for total magnesium in inland saline waters or inland saline sediment. The U.S. EPA's saltwater aquatic life criteria and saltwater California Toxics Rule (CTR) standards are being used to assess the SAL use for the Amargosa River. However, these criteria and standards are not appropriate for assessment of inland saline habitat, which support different aquatic biota compared to marine ecosystems. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. The number of samples are limited so data are not temporally representative of the conditions in the river, which are characterized by great seasonal and annual variability in flows. 3. There are no applicable state or federal aquatic life standards or criteria for total magnesium in inland saline waters. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because (1) the minimum sample number requirements of the Listing Policy are not met and (2) it cannot be determined if applicable water quality standards are being exceeded because there are no state or federal aquatic life criteria for inland saline waters or inland saline sediment.

Line of Evidence (LOE) for Decision ID 30778, Magnesium | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46686
Pollutant: | Magnesium
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Two samples had total magnesium concentrations of 44.1 and 57.5 mg/L.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no applicable state or federal standards or criteria for total magnesium in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 30778, Magnesium | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46685
Pollutant: | Magnesium
LOE Subgroup: | Pollutant-Sediment
Matrix: | Sediment
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Chemical monitoring of sediments
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled sediment at this station on March 16, 2005 under the Region 6 SWAMP program. Results were reported as "bed sediment, smaller than 62.5 um, wet sieved, total digestion." The concentration of magnesium was 0.98 percent dry weight.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal standards or criteria for magnesium in sediment in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sediment sample was collected on March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 30778, Magnesium | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46687
Pollutant: | Magnesium
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Two samples had dissolved magnesium concentrations of 35.and 53.4 mg/L.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no applicable state or federal standards or criteria for total magnesium in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30779 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Manganese
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Three lines of evidence, consisting of one sediment and two water samples, are available in the administrative record to assess this pollutant. However, it is difficult to assess whether applicable water quality standards are being exceeded or met because the number of samples are limited and there are no state or federal aquatic life criteria for inland saline waters or for inland saline sediment. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable state or federal saltwater aquatic life standards or criteria for manganese in inland saline waters or sediment. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because (1) the minimum sample number requirements of the Listing Policy are not met and (2) it cannot be determined if applicable water quality standards are being exceeded because there are no state or federal aquatic life criteria for inland saline waters or inland saline sediment.

Line of Evidence (LOE) for Decision ID 30779, Manganese | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46689
Pollutant: | Manganese
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Concentrations of total manganese in two samples were 70 and 175 ug/L.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no applicable state or federal saltwater aquatic life standards or criteria for total manganese in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 30779, Manganese | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46688
Pollutant: | Manganese
LOE Subgroup: | Pollutant-Sediment
Matrix: | Sediment
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Chemical monitoring of sediments
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled sediment at this station on March 16, 2005 under the Region 6 SWAMP program. Results were reported as "bed sediment, smaller than 62.5 um, wet sieved, total digestion." The concentration of manganese was 490 ug/g dry weight.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal standards or criteria for manganese in sediment in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sediment sample was collected on March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 30779, Manganese | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46690
Pollutant: | Manganese
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Concentrations of dissolved manganese in two samples were 49.8 and 153 ug/L.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no applicable state or federal saltwater aquatic life standards or criteria for dissolved manganese in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30780 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Mercury
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Three lines of evidence, consisting of one sediment and two water samples, are available in the administrative record to assess this pollutant. However, it is difficult to assess whether applicable water quality standards are being exceeded or met because the number of samples are limited and there are no state or federal aquatic life criteria for inland saline waters or for inland saline sediment. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. The number of samples are limited so data are not temporally representative of the conditions in the river, which are characterized by great seasonal and annual variability in flows. 3. There are no applicable state or federal saltwater aquatic life standards or criteria for mercury in inland saline waters or sediment. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because (1) the minimum sample number requirements of the Listing Policy are not met and (2) it cannot be determined if applicable water quality standards are being exceeded because there are no state or federal aquatic life criteria for inland saline waters or inland saline sediment.

Line of Evidence (LOE) for Decision ID 30780, Mercury | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46691
Pollutant: | Mercury
LOE Subgroup: | Pollutant-Sediment
Matrix: | Sediment
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Chemical monitoring of sediments
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled sediment at this station on March 16, 2005 under the Region 6 SWAMP program. Results were reported as "bed sediment, smaller than 62.5 um, wet sieved, total digestion." The concentration of mercury was below the detection level.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal standards or criteria for mercury in sediment in inland saline waters.
Objective/Criterion Reference: | Pollutants of concern in Puget Sound. EPA 910/9-91-003. Seattle, WA: U.S. Environmental Protection Agency
| Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sediment sample was collected on March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 30780, Mercury | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46692
Pollutant: | Mercury
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. One of two samples for dissolved mercury was below the detection level and the concentration in the other was an estimated value.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no applicable state or federal saltwater aquatic life standards or criteria for dissolved mercury in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 30780, Mercury | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46693
Pollutant: | Mercury
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. One of two samples for total mercury was below the detection level and the concentration in the other was an estimated value.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal standards or criteria for mercury for the protection of aquatic life in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30781 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Molybdenum
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Three lines of evidence, consisting of one sediment and two water samples, are available in the administrative record to assess this pollutant. However, it is difficult to assess whether applicable water quality standards are being exceeded or met because the number of samples are limited and there are no state or federal aquatic life criteria for inland saline waters or for inland saline sediment. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable state or federal saltwater aquatic life standards or criteria for molybdenum in inland saline waters or sediment. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because (1) the minimum sample number requirements of the Listing Policy are not met and (2) it cannot be determined if applicable water quality standards are being exceeded because there are no state or federal aquatic life criteria for inland saline waters or inland saline sediment.

Line of Evidence (LOE) for Decision ID 30781, Molybdenum | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46694
Pollutant: | Molybdenum
LOE Subgroup: | Pollutant-Sediment
Matrix: | Sediment
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Chemical monitoring of sediments
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled sediment at this station on March 16, 2005 under the Region 6 SWAMP program. Results were reported as "bed sediment, smaller than 62.5 um, wet sieved, total digestion." The concentration of molybdenum was 2.1 ug/g dry weight.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal standards or criteria for molybdenum in sediment in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sediment sample was collected on March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 30781, Molybdenum | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46695
Pollutant: | Molybdenum
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Concentrations of dissolved molybdenum in two samples were 49.6 and 57.5 ug/L.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no applicable state or federal saltwater aquatic life standards or criteria for dissolved molybdenum in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 30781, Molybdenum | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46696
Pollutant: | Molybdenum
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Concentrations of total molybdenum in two samples were 48.1 and 57.7 ug/L.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no applicable state or federal saltwater aquatic life standards or criteria for total molybdenum in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30792 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Neodymium
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. There are no state or federal standards or criteria for neodymium in sediment in inland saline waters. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The single sample does not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the data cannot be assessed using Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because (1) the minimum sample number requirements of the Listing Policy are not met and (2) it cannot be determined if applicable water quality standards are being exceeded because there are no state or federal aquatic life criteria for inland saline waters or inland saline sediment, and (3) and the data are not temporally representative of the conditions in the river, which are characterized by great seasonal and annual variability in flows.

Line of Evidence (LOE) for Decision ID 30792, Neodymium | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46697
Pollutant: | Neodymium
LOE Subgroup: | Pollutant-Sediment
Matrix: | Sediment
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Chemical monitoring of sediments
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled sediment at this station on March 16, 2005 under the Region 6 SWAMP program. Results were reported as "bed sediment, smaller than 62.5 um, wet sieved, total digestion." The concentration of neodymium was 33 ug/g dry weight.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal standards or criteria for neodymium in sediment in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sediment sample was collected on March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30784 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Nickel
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Three lines of evidence, including total and dissolved nickel in water and nickel in sediment, are available in the administrative record to assess this pollutant. However, it is difficult to assess whether applicable water quality standards are being exceeded or met because the number of samples are limited and there are no state or federal aquatic life criteria for inland saline waters or for inland saline sediment. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. Only one water sample per year was collected. 3. There are no state or federal aquatic life criteria for inland saline waters or for inland saline sediment. The evaluation criteria being used to evaluate whether the SAL use within the Amargosa River is supported is based on toxicity tests for marine/estuarine organisms and is not appropriate for inland saline waters. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because, although the California Toxics Rule standards are being exceeded, the standards are inappropriate for inland saline waters, and the data are not temporally representative.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because (1) the minimum sample number requirements of the Listing Policy are not met and (2) it cannot be determined if applicable water quality standards are being exceeded because there are no state or federal aquatic life criteria for inland saline waters or inland saline sediment.

Line of Evidence (LOE) for Decision ID 30784, Nickel | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46699
Pollutant: | Nickel
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Concentrations of total nickel in two samples were 2.4 and 2.75 ug/L.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no applicable state or federal saltwater aquatic life standards or criteria for total nickel in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 30784, Nickel | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46698
Pollutant: | Nickel
LOE Subgroup: | Pollutant-Sediment
Matrix: | Sediment
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Chemical monitoring of sediments
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled sediment at this station on March 16, 2005 under the Region 6 SWAMP program. Results were reported as "bed sediment, smaller than 62.5 um, wet sieved, total digestion." The concentration of nickel was 9 ug/g dry weight.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal standards or criteria for nickel in sediment in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sediment sample was collected on March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 30784, Nickel | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46700
Pollutant: | Nickel
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Concentrations of dissolved nickel in two samples were 1.32 and 1.52 ug/L.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | The California Toxics Rule's saltwater aquatic life standards for dissolved nickel include an acute toxicity limit of 74 ug/L and a achronic toxicity limit of 8.2 ug/L.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30876 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Nitrate/Nitrite (Nitrite + Nitrate as N)
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. There are no applicable state or federal saltwater aquatic life standards or criteria for nitrite plus nitrate. The Lahontan Basin Plan's regionwide objective for biostimulatory substances states: "Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect the water for beneficial uses." Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used does not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable state or federal saltwater aquatic life standards or criteria for nitrite plus nitrate to determine whether the SAL beneficial use for the Amargosa River is being supported or impaired. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded because there are no applicable state or federal saltwater aquatic life standards or criteria for nitrite plus nitrate.

Line of Evidence (LOE) for Decision ID 30876, Nitrate/Nitrite (Nitrite + Nitrate as N) | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46702
Pollutant: | Nitrate/Nitrite (Nitrite + Nitrate as N)
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Two samples had nitrite plus nitrate concentrations of 0.009 and 0.004 mg/L.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no applicable state or federal saltwater aquatic life standards or criteria for nitrite plus nitrate. The Lahontan Basin Plan's regionwide objective for biostimulatory substances states: "Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect the water for beneficial uses."
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30877 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Nitrite
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. There are no applicable state or federal saltwater aquatic life standards or criteria for nitrite in inland saline waters. The Lahontan Basin Plan's regionwide objective for biostimulatory substances states: "Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect the water for beneficial uses." Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable state or federal saltwater aquatic life standards or criteria for nitrite in inland saline waters to evaluate whether the SAL beneficial use for the Amargosa River is being supported or impaired. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded because there are no applicable state or federal saltwater aquatic life standards or criteria for nitrite in inland saline waters.

Line of Evidence (LOE) for Decision ID 30877, Nitrite | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46703
Pollutant: | Nitrite
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Two samples had nitrite concentrations of 0.002 and 0.001 mg/L.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no applicable state or federal saltwater aquatic life standards or criteria for nitrite in inland saline waters. The Lahontan Basin Plan's regionwide objective for biostimulatory substances states: "Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect the water for beneficial uses."
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30479 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Nitrogen, ammonia (Total Ammonia)
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | The LOE was incorrectly assigned to the waterbody so there is no data available for this waterbody/pollutant combination. The mapped representation of this waterbody was corrected this cycle. This decision is being decommissioned (to be retired next cycle) while a copy of it as a "Do Not List" now lives with the new mapped representation of this waterbody. This pollutant is being considered for placement on the section 303(d) list under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. Zero of one sample exceeded the objective and this sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 26 samples is needed for application of table 3.2 4. Pursuant to 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 30479, Nitrogen, ammonia (Total Ammonia) | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 32483
Pollutant: | Nitrogen, ammonia (Total Ammonia)
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Warm Freshwater Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | The single sample did not exceeded the water quality objective for unionized ammonia. Data were reported as as total ammonia as nitrogen and were converted to unionized ammonia before being compared with the objective.
Data Reference: | Statewide Perennial Streams Assessment 2008
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | The Lahontan Basin Plan objective for unionized ammonia is a function of pH, temperature, and the presence of salmonids. The 4-day chronic criteria for unionized ammonia with salmonids absent is 0.0709 mg/L.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | The sample was collected at site 609PS0053.
Temporal Representation: | The sample was collected on 5/14/2008.
Environmental Conditions: |
QAPP Information: | The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): | Surface Water Ambient Monitoring Program Quality Assurance Program Plan

DECISION ID | 30875 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Oxygen 18/Oxygen 16 ratio
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. There are no applicable state or federal saltwater aquatic life standards or criteria for Oxygen 18/Oxygen 16 ratio in inland saline waters. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used does not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable state or federal saltwater aquatic life standards or criteria for Oxygen 18/Oxygen 16 ratio in inland saline waters to determine if the SAL beneficial use is being supported or impaired. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because (1) the minimum sample number requirements of the Listing Policy are not met and (2) it cannot be determined if applicable water quality standards are being exceeded because there are no state or federal aquatic life criteria for inland saline waters or inland saline sediment.

Line of Evidence (LOE) for Decision ID 30875, Oxygen 18/Oxygen 16 ratio | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46704
Pollutant: | Oxygen 18/Oxygen 16 ratio
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on March 17, 2004 and March 15, 2005 under the Region 6 SWAMP program. The oxygen 18/oxygen 16 ratios in 2 samples were -11.62/mL and -11.64/mL.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal saltwater aquatic life standards or criteria for oxygen 1/oxygen 16 ratio in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek confluence, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30480 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Oxygen, Dissolved
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This pollutant is being considered for placement on the section 303(d) list under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. Two lines of evidence, one each to evaluate WARM and Inland Saline Habitat, are available in the administrative record to assess this pollutant. None of the samples exceed the water quality objective.Since there is no specific objective for Inland Saline Water Habitat, the water quality objective of 5.0 mg/L dissolved oxygen that is used to protect WARM is applied for protection of Inland Saline Water Habitat. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. None of the three samples exceeded the water quality objective for DO of 5.0 mg/L and this sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 26 samples is needed for application of table 3.2. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 30480, Oxygen, Dissolved | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 32354
Pollutant: | Oxygen, Dissolved
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Warm Freshwater Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | The single sample collected did not exceed the water quality objective.
Data Reference: | Statewide Perennial Streams Assessment 2008
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | The objective from Lahontan Basin Plan Table 3-6 for water bodies with the Warm and SPWN beneficial uses shall not be less than a one-day minimum dissolved oxygen concentration of 5.0 mg/L.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | Sample was collected at station 609PS0053 in Amargosa River.
Temporal Representation: | Sample collected on 8/4/2008.
Environmental Conditions: |
QAPP Information: | The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): | Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 30480, Oxygen, Dissolved | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46750
Pollutant: | Oxygen, Dissolved
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Concentrations of dissolved oxygen in two samples were 9.8 and 7.1 ug/L.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | The applicable water quality objective (from Lahontan Basin Plan Table 3-6) is a one-day minimum dissolved oxygen concentration of 5 mg/L.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30645 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Percent Sodium
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | The LOE was incorrectly assigned to the waterbody so there is no data available for this waterbody/pollutant combination. The mapped representation of this waterbody was corrected this cycle. This decision is being decommissioned (to be retired next cycle) while a copy of it as a "Do Not List" now lives with the new mapped representation of this waterbody. This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line(s) of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. One of the one sample exceeds the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfies the data quantity requirements of section 6.1.5 of the Policy. 3. One of one samples exceeded the criteria and this sample size is insufficient to determine with the power and confidence of the Listing Policy if standards are not met. A minimum of 16 samples is needed for application of table 3.1. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded. There is no site-specific water quality objective for Percent Sodium in the Amargosa River. Percent sodium is an older and now obsolete criterion for irrigation waters. It is an index for the percentage of sodium ion in the sum of the concentrations of sodium, calcium, magnesium and potassium ions. Waters with percent sodium greater than 70-75 percent were considered to be unsuitable for irrigation use.

Line of Evidence (LOE) for Decision ID 30645, Percent Sodium | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46624
Pollutant: | Percent Sodium
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Agricultural Supply
Number of Samples: | 1
Number of Exceedances: | 1
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on March 16, 2005 under the Region 6 SWAMP program.. Percent sodium in one sample was 79 percent. Percent sodium is an older and now obsolete criterion for irrigation waters. It is an index for the percentage of sodium ion in the sum of the concentrations of sodium, calcium, magnesium and potassium ions. Waters with percent sodium greater than 70-75 percent were considered to be unsuitable for irrigation use.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There is no site-specific water quality objective for Percent Sodium in the Amargosa River. Percent sodium is an older and now obsolete criterion for irrigation waters. It is an index for the percentage of sodium ion in the sum of the concentrations of sodium, calcium, magnesium and potassium ions. Waters with percent sodium greater than 70-75 percent were considered to be unsuitable for irrigation use.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
| Water Quality Criteria. Second Edition. California State Water Resources Control Board. Publication 3-A
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sample was collected on March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not, to Lahontan Water Board staff's knowledge, used for irrigated agriculture. The river's intermittent character and highly variable flows would make it unsuitable for irrigation even if water quality were not naturally poor. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30865 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Phosphate
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. There are no applicable state or federal saltwater aquatic life standards or criteria for phosphate in inland saline waters. The Lahontan Basin Plan's regionwide objective for biostimulatory substances states: "Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect the water for beneficial uses, but there are no biological data are available for assessment whether any of the chemical samples exceeds the water quality objective for biostimulatory substances. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. No biological data are available for assessment of compliance with the objective and the data cannot be evaluated using Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because there is a quality assurance problem with the data, there are no applicable sediment standards or criteria and no biological data are available for assessment of compliance with the water quality objective.

Line of Evidence (LOE) for Decision ID 30865, Phosphate | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46705
Pollutant: | Phosphate
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Two samples had dissolved phosphate concentrations of 0.187 and 0.180 mg/L.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no applicable state or federal saltwater aquatic life standards or criteria for phosphate in inland saline waters. The Lahontan Basin Plan's regionwide objective for biostimulatory substances states: "Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect the water for beneficial uses."
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30866 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Phosphorus
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. There are no applicable water quality standards or criteria for phosphorus in sediment of inland saline waters. No biological data are available for assessment whether any of the chemical samples exceeds the water quality objective for biostimulatory substances. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used do not satisfy the data quality requirements of section 6.1.4 of the Policy due to an error in the SWAMP QAPP regarding holding times for total phosphorus samples. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy (only one sample per year is available). 3. No biological data are available for assessment of compliance with the objective and the data cannot be evaluated using Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because there is a quality assurance problem with the data, there are no applicable sediment standards or criteria and no biological data are available for assessment of compliance with the water quality objective.

Line of Evidence (LOE) for Decision ID 30866, Phosphorus | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46707
Pollutant: | Phosphorus
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Two samples had total phosphorus concentrations of 0.258 and 0.236 mg/L.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no applicable state or federal saltwater aquatic life standards or criteria for total phosphorus in inland saline waters. The Lahontan Basin Plan's regionwide objective for biostimulatory substances states: "Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect the water for beneficial uses."
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | Sampling and analysis were done according to the SWAMP QAPP. However, in July 2009 an error was discovered in the QAPP related to holding times for total phosphorus samples that affects the validity of data for the Lahontan Region The holding time for samples that are not acid-preserved.should be 48 hours rather than 28 days as indicated in the QAPP. "Low level" phosphorus analyses, without acid preservation, are used in the Lahontan Region's SWAMP program. .
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 30866, Phosphorus | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46706
Pollutant: | Phosphorus
LOE Subgroup: | Pollutant-Sediment
Matrix: | Sediment
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Chemical monitoring of sediments
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled sediment at this station on March 16, 2005 under the Region 6 SWAMP program. Results were reported as "bed sediment, smaller than 62.5 um, wet sieved, total digestion." The concentration of phosphorus was 0.063 percent dry weight.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal standards or criteria for phosphorus in sediment in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sediment sample was collected on March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | Sampling and analysis were done according to the SWAMP QAPP. However, in July 2009 an error was discovered in the QAPP related to holding times for total phosphorus samples that affects the validity of data for the Lahontan Region The holding time for samples that are not acid-preserved.should be 48 hours rather than 28 days as indicated in the QAPP. "Low level" phosphorus analyses, without acid preservation, are used in the Lahontan Region's SWAMP program. .
QAPP Information Reference(s):

DECISION ID | 30868 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Potassium
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. Two lines of evidence are available in the administrative record to assess this pollutant. There are no applicable water quality standards or criteria. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable standards or criteria and the data cannot be assessed using Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because there are no applicable water quality standards or criteria and the minimum sample number requirements of the Listing Policy are not met.

Line of Evidence (LOE) for Decision ID 30868, Potassium | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46709
Pollutant: | Potassium
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Two samples had dissolved potassium concentrations of 42.5 and 43.1 mg/L.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no applicable state or federal standards or criteria for potassium in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 30868, Potassium | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46708
Pollutant: | Potassium
LOE Subgroup: | Pollutant-Sediment
Matrix: | Sediment
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Chemical monitoring of sediments
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled sediment at this station on March 16, 2005 under the Region 6 SWAMP program. Results were reported as "bed sediment, smaller than 62.5 um, wet sieved, total digestion." The concentration of potassium was 3 percent dry weight.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal standards or criteria for potassium in sediment in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sediment sample was collected on March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30863 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Radium 226
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. No biological data are available for assessment whether either of the samples exceeds the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. Only one sample per year is available. 3. No biological data are available for evaluation of compliance with the water quality objective and the data cannot be assessed using Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because there are no applicable water quality standards or criteria and the minimum sample number requirements of the Listing Policy are not met.

Line of Evidence (LOE) for Decision ID 30863, Radium 226 | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46710
Pollutant: | Radium 226
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Two samples had radium 226 levels of 0.09 and 0.051 pCi/L..
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal saltwater aquatic life standards or criteria specifically for radium 226 in inland saline waters. The Lahontan Basin Plan's narrative objective for radioactivity provdes that: "Radionuclides shall not be present in concentrations which are deleterious to human, plant, animal, or aquatic life nor which result in the accumulation of radionuclides in the food web to an estent which presents a hazard to human, plant, animal or aquatic life." The objective also incorporates California Maximum Contaminant Levels for waters designated for the MUN use. MCLs do not apply to the Amargosa River.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30833 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Scandium
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | "This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence, consisting of a single sediment sample, is available in the administrative record to assess this pollutant. There are no applicable water quality standards or criteria for scandium in the sediment of inland saline waters. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the single sample cannot be assessed using Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. ."
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because there are no applicable water quality standards or criteria and the minimum sample number requirements of the Listing Policy are not met.

Line of Evidence (LOE) for Decision ID 30833, Scandium | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46711
Pollutant: | Scandium
LOE Subgroup: | Pollutant-Sediment
Matrix: | Sediment
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Chemical monitoring of sediments
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled sediment at this station on March 16, 2005 under the Region 6 SWAMP program. Results were reported as "bed sediment, smaller than 62.5 um, wet sieved, total digestion." The concentration of scandium was 6 ug/g dry weight.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal standards or criteria for scandium in sediment in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sediment sample was collected on March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30864 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Sediment
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). The Lahontan Basin Plan's narrative water quality objective is an antidegradation based objective that provides that there shall be no increases in suspended sediment concentrations or loads. This pollutant is being considered for placement on the section 303(d) list under section 3.10 of the Listing Policy, which deals with trends in water quality. One line of evidence, based on two annual samples, is available in the administrative record to assess this pollutant. It includes two suspended sediment concentration values and two suspended sediment load values calculated from instantaneous discharge measurements. Suspended sediment concentrations and loads are dependent on flows and can change rapidly over a short time during storm runoff events. Annual samples are insufficient to capture these short term events and therefore are insufficient to define natural background suspended sediment concentrations and loads, or to detect trends. Listing Policy Section 3.10 requires that natural background conditions be established. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. Sampling frequency was insufficient to establish natural background conditions and therefore does not meet the requirements of Listing Policy Section 3.10. 3. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because (1) the minimum sample number requirements of the Listing Policy are not met and (2) annual samples are insufficient to establish natural background conditions and detect trends.

Line of Evidence (LOE) for Decision ID 30864, Sediment | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46712
Pollutant: | Sediment
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Suspended sediment concentrations in two samples were 25 and 46 mg/L. One of the instantaneous flow figures was an estimate and the other was 4.1 cubic feet per second. One of the calculated suspended sediment loads was an estimate and the other was 0.51 tons per day.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | The Lahontan Basin Plan's narrative objective states: "The suspended sediment load and suspended sediment discharge rate of surface waters shall not be altered in such a manner as to cause nuisance or adversely affect the water for beneficial uses."
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek confluence, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30790 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Selenium
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Three lines of evidence, including total and dissolved selenium in water and selenium in sediment, are available in the administrative record to assess this pollutant. The standards being used to evaluate whether the SAL use is supported in the Amargosa River is based on toxicity tests for marine/estuarine organisms and is not appropriate for inland saline waters, which support different aquatic biota compared to marine ecosystems. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. Only one water sample per year was collected. 3. There are no state or federal aquatic life criteria for protection of inland saline habitat. The standard being applied to assess whether the SAL beneficial use is supported in the Amargosa River is inappropriate for inland saline waters because it was developed using marine and estuarine organisms, and inland saline waters support different aquatic biota. Inland saline water organisms are adapted to greater extremes of and fluctuations in environmental conditions than marine organisms. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because (1) the minimum sample number requirements of the Listing Policy are not met and (2) it cannot be determined if applicable water quality standards are being exceeded because there are no state or federal aquatic life criteria for inland saline waters or inland saline sediment, and (3) and the data are not temporally representative of the conditions in the river, which are characterized by great seasonal and annual variability in flows.

Line of Evidence (LOE) for Decision ID 30790, Selenium | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46715
Pollutant: | Selenium
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Two samples had dissolved selenium concentrations of 0.8 and 1.4 ug/L.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | The California Toxics Rule's saltwater aquatic life standards for dissolved selenium include an acute toxicity limit of 290 ug/L and a chronic toxicity limit of 71 ug/L.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 30790, Selenium | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46714
Pollutant: | Selenium
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. One of 2 samples for total selenium was below the detection level and the other had a concentration of 1.9 ug/L.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no applicable state or federal saltwater aquatic life standards or criteria for total selenium in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 30790, Selenium | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46713
Pollutant: | Selenium
LOE Subgroup: | Pollutant-Sediment
Matrix: | Sediment
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Chemical monitoring of sediments
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled sediment at this station on March 16, 2005 under the Region 6 SWAMP program. Results were reported as "bed sediment, smaller than 62.5 um, wet sieved, total digestion." The concentration of selenium was below the detection level.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal standards or criteria for selenium in sediment in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sediment sample was collected on March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30799 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Silica
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. There are no applicable water quality standards or criteria for silica. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the data cannot be assessed using Table 3.2 of the Listing Policy. The minimum sample number requirements of Table 3.2 are not met. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because (1) the minimum sample number requirements of the Listing Policy are not met and (2) it cannot be determined if applicable water quality standards are being exceeded because there are no state or federal aquatic life criteria for inland saline waters or inland saline sediment.

Line of Evidence (LOE) for Decision ID 30799, Silica | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46716
Pollutant: | Silica
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Two samples had dissolved silica concentrations of 52.7 and 54.6 mg/L.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no applicable state or federal saltwater aquatic life standards or criteria for silica in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30798 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Silver
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Three lines of evidence, including total and dissolved silver in water and silver in sediment, are available in the administrative record to assess this pollutant. However, it is difficult to assess whether applicable water quality standards are being exceeded or met because the number of samples are limited and there are no state or federal aquatic life criteria for inland saline waters or for inland saline sediment. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. Only one water sample per year was collected, so data are not temporally representative of the conditions in the river, which are characterized by great seasonal and annual variability in flows. 3. There are no state or federal aquatic life criteria for inland saline waters or for inland saline sediment. The evaluation criteria being used to evaluate whether the SAL use within the Amargosa River is supported is based on toxicity tests for marine/estuarine organisms and is not appropriate for inland saline waters. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because (1) the minimum sample number requirements of the Listing Policy are not met, (2) it cannot be determined if applicable water quality standards are being exceeded because there are no state or federal aquatic life criteria for inland saline waters or inland saline sediment, (3) and the data are not temporally representative of the conditions in the Amargosa River, which are characterized by great seasonal and annual variability in flows.

Line of Evidence (LOE) for Decision ID 30798, Silver | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46719
Pollutant: | Silver
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Concentrations of dissolved silver in two samples were both below the detection level.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | The California Toxics Rule's saltwater aquatic life standard for silver is an acute toxicity limit of 1.9 ug/L.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 30798, Silver | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46718
Pollutant: | Silver
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Concentrations of total silver in two samples were both below the detection level.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no applicable state or federal saltwater aquatic life standards or criteria for total silver in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 30798, Silver | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46717
Pollutant: | Silver
LOE Subgroup: | Pollutant-Sediment
Matrix: | Sediment
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Chemical monitoring of sediments
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled sediment at this station on March 16, 2005 under the Region 6 SWAMP program. Results were reported as "bed sediment, smaller than 62.5 um, wet sieved, total digestion." The concentration of lead was 0.2 ug/g dry weight.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal standards or criteria for silver in sediment in inland saline waters. The Probable Effects Level for silver in marine and estuarine sediments is 1.77 ug/g dry weight; see MacDonald et al. (1996).
Objective/Criterion Reference: | Development and evaluation of sediment quality guidelines for Florida coastal waters. Ecotoxicology 5: 253-278
| Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sediment sample was collected on March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30834 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Sodium
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | "This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Three lines of evidence, consisting of a single sediment sample, a two water samples are available in the administrative record to assess this pollutant. There are no applicable state or federal aquatic life standards or criteria for sodium for inland saline waters or inland saline sediment. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. The number of samples are limited so data are not temporally representative of the conditions in the river, which are characterized by great seasonal and annual variability in flows. 3. There are no applicable state or federal aquatic life standards or criteria to access inland saline waters. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. ."
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because there are no applicable water quality standards or criteria and the minimum sample number requirements of the Listing Policy are not met.

Line of Evidence (LOE) for Decision ID 30834, Sodium | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46721
Pollutant: | Sodium
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Two samples had dissolved sodium concentrations of 851 and 759 mg/L.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no applicable state or federal saltwater aquatic life standards or criteria for sodium in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 30834, Sodium | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46720
Pollutant: | Sodium
LOE Subgroup: | Pollutant-Sediment
Matrix: | Sediment
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Chemical monitoring of sediments
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled sediment at this station on March 16, 2005 under the Region 6 SWAMP program. Results were reported as "bed sediment, smaller than 62.5 um, wet sieved, total digestion." The concentration of sodium was 2 percent dry weight.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal standards or criteria for sodium in sediment in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sediment sample was collected on March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30857 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Sodium Adsorption Ratio (SAR)
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). One line of evidence is available in the administrative record to assess this pollutant. The single sample exceeds the water quality criterion. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. The single sample is not temporally representative of the conditions in the river, which are characterized by great seasonal and annual variability in flows. 3. There are no applicable water quality standards or criteria and the minimum sample number requirement of Table 3.2 was not met. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 30857, Sodium Adsorption Ratio (SAR) | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46625
Pollutant: | Sodium Adsorption Ratio (SAR)
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Agricultural Supply
Number of Samples: | 1
Number of Exceedances: | 1
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on March 16, 2005 under the Region 6 SWAMP program. One sample had an SAR value of 17.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | Sodium Adsorption Ratio (SAR) is a criterion for irrigation waters that has replaced Percent Sodium. It quantifies the relative proportions of sodium, calcium, and magnesium ions. SAR values greater than 9 can impose severe restrictions on the use of irrigation water due to sodium toxicity to crops.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sample was collected on March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not, to Lahontan Water Board staff's knowledge, use for irrigated agriculture. Its intermittent nature and highly variable flows would make it unsuitable for irrigation even if water quality were not naturally poor. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30858 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Specific Conductance
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. There are no applicable state or federal aquatic life standards or criteria for inland surface waters. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. Only one sample per year was collected, so data are not temporally representative of the conditions in the river, which are characterized by great seasonal and annual variability in flows. 3. There are no applicable standards or criteria and the data cannot be assessed using Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because (1) the minimum sample number requirements of the Listing Policy are not met and (2) it cannot be determined if applicable water quality standards are being exceeded because there are no state or federal aquatic life criteria for inland saline waters.

Line of Evidence (LOE) for Decision ID 30858, Specific Conductance | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46722
Pollutant: | Specific Conductance
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Two specific conductance measurements were 4000 and 3680 uS/cm, reflecting the saline character of the river..
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no applicable state or federal saltwater aquatic life standards or criteria for specific conductance in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two specific conductance measurements were taken on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30835 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Strontium
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | "This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence, consisting of a single sediment sample, is available in the administrative record to assess this pollutant. There are no applicable water quality standards or criteria for strontium in the sediment of inland saline waters. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the single sample cannot be assessed using Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. ."
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because there are no applicable water quality standards or criteria and the minimum sample number requirements of the Listing Policy are not met.

Line of Evidence (LOE) for Decision ID 30835, Strontium | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46723
Pollutant: | Strontium
LOE Subgroup: | Pollutant-Sediment
Matrix: | Sediment
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Chemical monitoring of sediments
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled sediment at this station on March 16, 2005 under the Region 6 SWAMP program. Results were reported as "bed sediment, smaller than 62.5 um, wet sieved, total digestion." The concentration of strontium was 560 ug/g dry weight.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal standards or criteria for strontium in sediment in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sediment sample was collected on March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30862 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Sulfates
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. One line of evidence, consisting of two samples, is available in the administrative record to assess this pollutant. There are no applicable water quality standards or criteria for sulfate in inland saline waters. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. The number of samples are limited so data are not temporally representative of the conditions in the river, which are characterized by great seasonal and annual variability in flows. 3. There are no applicable water quality standards or criteria and the data cannot be assessed using Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because there are no applicable water quality standards or criteria, and the minimum sample number requirements of the Listing Policy are not met.

Line of Evidence (LOE) for Decision ID 30862, Sulfates | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46724
Pollutant: | Sulfates
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Two samples had dissolved sulfate concentrations of 796 and 844 mg/L.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no applicable state or federal saltwater aquatic life standards or criteria for sulfate in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30836 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Sulfur
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | "This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence, consisting of a single sediment sample, is available in the administrative record to assess this pollutant. There are no applicable water quality standards or criteria for sulfur in the sediment of inland saline waters. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the single sample cannot be assessed using Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. ."
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because there are no applicable water quality standards or criteria and the minimum sample number requirements of the Listing Policy are not met.

Line of Evidence (LOE) for Decision ID 30836, Sulfur | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46725
Pollutant: | Sulfur
LOE Subgroup: | Pollutant-Sediment
Matrix: | Sediment
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Chemical monitoring of sediments
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled sediment at this station on March 16, 2005 under the Region 6 SWAMP program. Results were reported as "bed sediment, smaller than 62.5 um, wet sieved, total digestion." The concentration of sulfur was less than 0.05 percent dry weight.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal standards or criteria for sulfur in sediment in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sediment sample was collected on March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30837 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Tantalum
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | "This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence, consisting of a single sediment sample, is available in the administrative record to assess this pollutant. There are no applicable water quality standards or criteria for tantalum in the sediment of inland saline waters. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the single sample cannot be assessed using Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. ."
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because there are no applicable water quality standards or criteria and the minimum sample number requirements of the Listing Policy are not met.

Line of Evidence (LOE) for Decision ID 30837, Tantalum | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46726
Pollutant: | Tantalum
LOE Subgroup: | Pollutant-Sediment
Matrix: | Sediment
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Chemical monitoring of sediments
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled sediment at this station on March 16, 2005 under the Region 6 SWAMP program. Results were reported as "bed sediment, smaller than 62.5 um, wet sieved, total digestion." The concentration of tantalum was below the detection levelt.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal standards or criteria for tantalum in sediment in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sediment sample was collected on March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30878 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Temperature, water
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. One line of evidence, consisting of two annual samples, is available to support this decision. There are not enough temperature samples to establish baseline conditions (including diel, seasonal, annual and interannual variations in temperature) or to detect declining trends in the temperature regime if such trends exist. The Lahontan Basin Plan's narrative temperature objective is an antidegradation-based objective that requires that there be no change in temperature in waters designated for the Warm Freshwater Habitat (WARM) beneficial use. The objective does not include specific numerical limits for protection of the WARM use. Listing Policy Section 3.10 contains directions for assessment based on trends in water quality. These directions include requirements to establish specific baseline conditions and specify the influence of seasonal and interannual effects. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used do not satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. Too few samples are available to define the natural range of temperature (including diel, seasonal and annual varations) or to detect whether changes have occurred. 3. The available samples are insufficient to determine compliance with the objective under section 3.10 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. .
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded because there are not enough temperature samples to establish baseline conditions (including diel, seasonal, annual and interannual variations in temperature) or to detect declining trends in the temperature regime if such trends exist.

Line of Evidence (LOE) for Decision ID 30878, Temperature, water | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46752
Pollutant: | Temperature, water
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Two samples had temperatures of 17 and 16 degrees Celsius.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | The temperature objective in the Lahontan Basin Plan states: "The natural receiving water temperature of all waters shall not be altered unless it can be demonstrated to the satisfaction of the Regional Board that such an alteration in temperature does not adversely affect the water for beneficial uses. For waters designated WARM, water temperature shall not be altered by more than five degrees Fahrenheit ... above or below the natural temperature. For waters designated COLD, the temperature shall not be altered. Temperature objectives for COLD interstate waters and WARM interstate waters are as specified in the 'Water Quality Control Plan for Control of Temperature in The Coastal and Interstate Waters and Enclosed Bays and Estuaries of California' including any revisions."
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two temperature measurements were taken on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30797 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Thallium
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Three lines of evidence, including total and dissolved thallium in water and thallium in sediment, are available in the administrative record to assess this pollutant. However, it is difficult to assess whether applicable water quality standards are being exceeded or met because there are no state or federal aquatic life criteria for inland saline waters or for inland saline sediment. Additionally, the number of samples are limited so data are not temporally representative of the conditions in the river, which are characterized by great seasonal and annual variability in flows. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. Only one water sample per year was collected. 3. There are no state or federal aquatic life criteria for inland saline waters or for inland saline sediment. The evaluation criteria being used to evaluate whether the SAL use within the Amargosa River is supported is based on toxicity tests for marine/estuarine organisms and is not appropriate for inland saline waters. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because (1) the minimum sample number requirements of the Listing Policy are not met, (2) it cannot be determined if applicable water quality standards are being exceeded because there are no state or federal aquatic life criteria for inland saline waters or inland saline sediment, (3) and the data are not temporally representative of the conditions in the Amargosa River, which are characterized by great seasonal and annual variability in flows.

Line of Evidence (LOE) for Decision ID 30797, Thallium | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46729
Pollutant: | Thallium
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Concentrations of total thallium in two samples were both below the detection level.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no applicable state or federal saltwater aquatic life standards or criteria for total thallium in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 30797, Thallium | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46728
Pollutant: | Thallium
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. The concentration of dissolved thallium in one of two samples was below the detection level, and the other sample was an estimated value.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no applicable state or federal saltwater aquatic life standards or criteria for dissolved thallium in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 30797, Thallium | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46727
Pollutant: | Thallium
LOE Subgroup: | Pollutant-Sediment
Matrix: | Sediment
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Chemical monitoring of sediments
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled sediment at this station on March 16, 2005 under the Region 6 SWAMP program. Results were reported as "bed sediment, smaller than 62.5 um, wet sieved, total digestion." The concentration of thallium was below the detection levelt.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal standards or criteria for thallium in sediment in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sediment sample was collected on March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30839 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Thorium
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | "This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence, consisting of a single sediment sample, is available in the administrative record to assess this pollutant. There are no applicable water quality standards or criteria for thorium in the sediment of inland saline waters. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the single sample cannot be assessed using Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. ."
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because there are no applicable water quality standards or criteria and the minimum sample number requirements of the Listing Policy are not met.

Line of Evidence (LOE) for Decision ID 30839, Thorium | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46731
Pollutant: | Thorium
LOE Subgroup: | Pollutant-Sediment
Matrix: | Sediment
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Chemical monitoring of sediments
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled sediment at this station on March 16, 2005 under the Region 6 SWAMP program. Results were reported as "bed sediment, smaller than 62.5 um, wet sieved, total digestion." The concentration of thorium was 10 ug/g dry weight.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal standards or criteria for thorium in sediment in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sediment sample was collected on March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30838 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Tin
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | "This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence, consisting of a single sediment sample, is available in the administrative record to assess this pollutant. There are no applicable state or federal aquatic life standards or criteria for tin in the sediment of inland saline waters. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the single sample cannot be assessed using Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. ."
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because there are no applicable water quality standards or criteria and the minimum sample number requirements of the Listing Policy are not met.

Line of Evidence (LOE) for Decision ID 30838, Tin | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46732
Pollutant: | Tin
LOE Subgroup: | Pollutant-Sediment
Matrix: | Sediment
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Chemical monitoring of sediments
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled sediment at this station on March 16, 2005 under the Region 6 SWAMP program. Results were reported as "bed sediment, smaller than 62.5 um, wet sieved, total digestion." The concentration of tin was 2 ug/g dry weight.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal standards or criteria for tin in sediment in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sediment sample was collected on March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30832 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Titanium
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | "This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence, consisting of a single sediment sample, is available in the administrative record to assess this pollutant. There are no applicable water quality standards or criteria for titanium in the sediment of inland saline waters. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the single sample cannot be assessed using Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. ."
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because there are no applicable water quality standards or criteria and the minimum sample number requirements of the Listing Policy are not met.

Line of Evidence (LOE) for Decision ID 30832, Titanium | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46733
Pollutant: | Titanium
LOE Subgroup: | Pollutant-Sediment
Matrix: | Sediment
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Chemical monitoring of sediments
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled sediment at this station on March 16, 2005 under the Region 6 SWAMP program. Results were reported as "bed sediment, smaller than 62.5 um, wet sieved, total digestion." The concentration of titanium was 0.24 percent dry weight.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal standards or criteria for titanium in sediment in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sediment sample was collected on March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30859 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Total Dissolved Solids
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.2 of the Listing Policy. Under section 3.2 a single line of evidence is necessary to assess listing status. One line of evidence, consisting of two samples, is available in the administrative record to assess this pollutant. A third sample was analyzed by a different method. There are no applicable water quality standards or criteria for total dissolved solids in inland saline waters. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the data cannot be assessed using Table 3.2 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because there are no applicable water quality standards or criteria, and the minimum sample number requirements of the Listing Policy are not met.

Line of Evidence (LOE) for Decision ID 30859, Total Dissolved Solids | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46734
Pollutant: | Total Dissolved Solids
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total Dissolved
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Two samples had TDS concentrations of 2840 and 2550 mg/L. A third sample was reported as "residue", with a concentration of 2550 mg/L.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no applicable state or federal saltwater aquatic life standards or criteria for total dissolved solids (TDS) in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30860 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Total Kjeldahl Nitrogen (TKN)
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. No biological data are available for assessment whether any of the chemical samples exceeds the water quality objective. There are no state or federal aquatic life criteria for inland saline waters or for inland saline sediment. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy (only one sample per year is available). 3. No biological data are available for assessment of compliance with the objective and the data cannot be evaluated using Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because no biological data are available for assessment of compliance with the objective.

Line of Evidence (LOE) for Decision ID 30860, Total Kjeldahl Nitrogen (TKN) | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46735
Pollutant: | Total Kjeldahl Nitrogen (TKN)
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Two samples had TKN concentrations of 0.57 and 0.35 mg/L.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no applicable state or federal saltwater aquatic life standards or criteria for total Kjeldahl nitrogen (TKN). The Lahontan Basin Plan's regionwide objective for biostimulatory substances states: "Waters shall not contain biostimulatory substances in concentrations that promote aquatic growths to the extent that such growths cause nuisance or adversely affect the water for beneficial uses."
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30880 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Triclopyr
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. There are no state or federal saltwater aquatic life standards or criteria for the herbicide triclopyr in inland saline waters. The Lahontan Basin Plan's narrative objective for pesticides provides that: "Pesticide concentrations, individually or collectively, shall not exceed the lowest detectable levels, using the most recent detection procedures available." Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfies the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no state or federal saltwater aquatic life standards or criteria for the herbicide triclopyr in inland saline waters to determine if the SAL beneficial use is being supported or impaired in the Amargosa River. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded.

Line of Evidence (LOE) for Decision ID 30880, Triclopyr | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46736
Pollutant: | Triclopyr
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 1
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on March 17, 2004 under the Region 6 SWAMP program. The single sample had a detectable triclopyr concentration of 0.06 ug/L.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal saltwater aquatic life standards or criteria for the herbicide triclopyr in inland saline waters. The Lahontan Basin Plan's narrative objective for pesticides provides that: "Pesticide concentrations, individually or collectively, shall not exceed the lowest detectable levels, using the most recent detection procedures available."
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek confluence, was sampled.
Temporal Representation: | One sample was collected on March 18, 2004.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30879 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Tritium
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: |
Regional Board Staff Decision Recommendation: |

Line of Evidence (LOE) for Decision ID 30879, Tritium | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46737
Pollutant: | Tritium
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Two samples had tritium counts of 1.6 and 1.7 pCi/L. The tritium 2 sigma combined uncertainties were 0.58 and 0.64 pCi/L.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal saltwater aquatic life standards or criteria specifically for tritium in inland saline waters. The Lahontan Basin Plan's narrative objective for radioactivity provdes that: "Radionuclides shall not be present in concentrations which are deleterious to human, plant, animal, or aquatic life nor which result in the accumulation of radionuclides in the food web to an estent which presents a hazard to human, plant, animal or aquatic life." The objective also incorporates California Maximum Contaminant Levels for waters designated for the MUN use. MCLs do not apply to the Amargosa River.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30861 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Turbidity
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). Two lines of evidence are available in the administrative record to assess this pollutant. The narrative water quality objective for turbidity is an antidegradation-based objective and the two available samples are insufficient to document baseline and trend conditions as required under Listing Policy Section 3.10. The two turbidity measurements were taken using different methods and are not comparable. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. Samples were collected only once a year. 3. The requirements of Listing Policy section 3.10 to document baseline and trend conditions are not met in relation to the narrative water quality objective. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded because there are not enough data points to determine if baseline and trend conditions are not met in relation to the narrative water quality objective.

Line of Evidence (LOE) for Decision ID 30861, Turbidity | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46738
Pollutant: | Turbidity
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 Turbidity was 14 NTU.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | The Lahontan Basin Plan's regionwide turbidity objective states: "Waters shall be free of changes in turbidity that cause nuisance or adversely affect the water for beneficial uses. Increases in turbidity shall not exceed natural levels by more than 10 percent."
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One turbidity measurement was taken on March 18, 2004.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 30861, Turbidity | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46739
Pollutant: | Turbidity
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March16, 2005 Turbidity was 9.7 NTRU.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | The Lahontan Basin Plan's regionwide turbidity objective states: "Waters shall be free of changes in turbidity that cause nuisance or adversely affect the water for beneficial uses. Increases in turbidity shall not exceed natural levels by more than 10 percent."
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One turbidity measurement was taken on March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30830 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Uranium
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | "This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence, consisting of a single sediment sample, is available in the administrative record to assess this pollutant. There are no applicable water quality standards or criteria for uranium in the sediment of inland saline waters. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the single sample cannot be assessed using Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. ."
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because there are no applicable water quality standards or criteria and the minimum sample number requirements of the Listing Policy are not met.

Line of Evidence (LOE) for Decision ID 30830, Uranium | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46740
Pollutant: | Uranium
LOE Subgroup: | Pollutant-Sediment
Matrix: | Sediment
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Chemical monitoring of sediments
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled sediment at this station on March 16, 2005under the Region 6 SWAMP program. Results were reported as "bed sediment, smaller than 62.5 um, wet sieved, total digestion." The concentration of uranium was 2.7 ug/g dry weight.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal standards or criteria for uranium in sediment in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sediment sample was collected on March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30795 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Vanadium
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Three lines of evidence, including total and dissolved vanadium in water and vanadium in sediment, are available in the administrative record to assess this pollutant. However, it is difficult to assess whether applicable water quality standards are being exceeded or met because the number of samples are limited and there are no state or federal aquatic life criteria for inland saline waters or for inland saline sediment. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. Only one water sample per year was collected. 3. There are no state or federal aquatic life criteria for inland saline waters or for inland saline sediment. The evaluation criteria being used to evaluate whether the SAL use within the Amargosa River is supported is based on toxicity tests for marine/estuarine organisms and is not appropriate for inland saline waters. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because (1) the minimum sample number requirements of the Listing Policy are not met, (2) it cannot be determined if applicable water quality standards are being exceeded because there are no state or federal aquatic life criteria for inland saline waters or inland saline sediment, (3) and the data are not temporally representative of the conditions in the Amargosa River, which are characterized by great seasonal and annual variability in flows.

Line of Evidence (LOE) for Decision ID 30795, Vanadium | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46741
Pollutant: | Vanadium
LOE Subgroup: | Pollutant-Sediment
Matrix: | Sediment
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Chemical monitoring of sediments
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled sediment at this station on March 16, 2005 under the Region 6 SWAMP program. Results were reported as "bed sediment, smaller than 62.5 um, wet sieved, total digestion." The concentration of vanadium was 43 ug/g dry weight.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal standards or criteria for vanadium in sediment in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sediment sample was collected on March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 30795, Vanadium | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46743
Pollutant: | Vanadium
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. The concentration of total vanadium in 1 of 2 samples was 10 ug/L; vanadium was detected but not quantified in the other sample.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no applicable state or federal saltwater aquatic life standards or criteria for total vanadium in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 30795, Vanadium | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46742
Pollutant: | Vanadium
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. The concentration of dissolved vanadium in two samples were 12.4 and 13.2 ug/L
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no applicable state or federal saltwater aquatic life standards or criteria for dissolved vanadium in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30829 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Ytterbium
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence, consisting of a single sediment sample, is available in the administrative record to assess this pollutant. There are no applicable water quality standards or criteria for ytterbium in the sediment of inland saline waters. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the single sample cannot be assessed using Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because there are no applicable water quality standards or criteria and the minimum sample number requirements of the Listing Policy are not met.

Line of Evidence (LOE) for Decision ID 30829, Ytterbium | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46744
Pollutant: | Ytterbium
LOE Subgroup: | Pollutant-Sediment
Matrix: | Sediment
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Chemical monitoring of sediments
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled sediment at this station on March 16, 2005 under the Region 6 SWAMP program. Results were reported as "bed sediment, smaller than 62.5 um, wet sieved, total digestion." The concentration of ytterbium was 2 ug/g dry weight.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal standards or criteria for ytterbium in sediment in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sediment sample was collected on March 16, 2005
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30828 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Yttrium
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence, consisting of a single sediment sample, is available in the administrative record to assess this pollutant. There are no applicable water quality standards or criteria for yttrium in the sediment of inland saline waters. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the single sample cannot be assessed using Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because there are no applicable water quality standards or criteria and the minimum sample number requirements of the Listing Policy are not met.

Line of Evidence (LOE) for Decision ID 30828, Yttrium | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46745
Pollutant: | Yttrium
LOE Subgroup: | Pollutant-Sediment
Matrix: | Sediment
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Chemical monitoring of sediments
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled sediment at this station on March 16, 2005 under the Region 6 SWAMP program. Results were reported as "bed sediment, smaller than 62.5 um, wet sieved, total digestion." The concentration of yttrium was 16 ug/g dry weight.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal standards or criteria for yttrium in sediment in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sediment sample was collected on March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30791 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Zinc
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. Three lines of evidence, including total and dissolved zinc in water and zinc in sediment, are available in the administrative record to assess this pollutant. The standards being used to evaluate whether the SAL use is supported in the Amargosa River is based on toxicity tests for marine/estuarine organisms and is not appropriate for inland saline waters, which support different aquatic biota compared to marine ecosystems. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy. Only one water sample per year was collected. 3. There are no state or federal aquatic life criteria for protection of inland saline habitat. The standard being applied to assess whether the SAL beneficial use is supported in the Amargosa River is inappropriate for inland saline waters because it was developed using marine and estuarine organisms, and inland saline waters support different aquatic biota. Inland saline water organisms are adapted to greater extremes of and fluctuations in environmental conditions than marine organisms. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because (1) the minimum sample number requirements of the Listing Policy are not met and (2) it cannot be determined if applicable water quality standards are being exceeded because there are no state or federal aquatic life criteria for inland saline waters or inland saline sediment, and (3) and the data are not temporally representative of the conditions in the river, which are characterized by great seasonal and annual variability in flows.

Line of Evidence (LOE) for Decision ID 30791, Zinc | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46746
Pollutant: | Zinc
LOE Subgroup: | Pollutant-Sediment
Matrix: | Sediment
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Chemical monitoring of sediments
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled sediment at this station on March 16, 2005 under the Region 6 SWAMP program. Results were reported as "bed sediment, smaller than 62.5 um, wet sieved, total digestion." The concentration of zinc was ug/g dry weight.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal standards or criteria for znc in sediment in inland saline waters. The Effects Range-Median for zinc in marine and estuarine sediments is 410 ug/g dry weight; see Long et al. (1995).
Objective/Criterion Reference: | Incidence of adverse biological effects within ranges of chemical concentrations in marine and estuary sediments. Environmental Management. 19, (1): 81-97
| Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sediment sample was collected on March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 30791, Zinc | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46748
Pollutant: | Zinc
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Total
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. The concentration of total zinc in one of two samples was 4 ug/L and the other sample was an estimated value.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal saltwater aquatic life standards or criteria for total zinc in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):
Line of Evidence (LOE) for Decision ID 30791, Zinc | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46747
Pollutant: | Zinc
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | Dissolved
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. The concentrations of dissolved zinc in two samples were 2 and 2.8 ug/L.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | The California Toxics Rule's saltwater aquatic life standards for dissolved zinc include an acute toxicity limit of 90 ug/L and a chronic toxicity limit of 81 ug/L.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30481 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | pH
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Revised
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). The Lahontan Basin Plan's narrative pH objective is an antidegradation-based objective that requires that there be no change greater than 0.5 pH units in waters designated for the Cold Freshwater Habitat (COLD) or Warm Freshwater Habitat (WARM) beneficial uses. A pH range of 6.5 to 8.5 units applies to "all other waters." Listing Policy Section 3.10 contains directions for assessment based on trends in water quality. These directions include requirements to establish specific baseline conditions and specify the influence of seasonal and interannual effects. The Amargosa River is designated for both the Warm Freshwater Habitat (WARM) and Inland Saline Water Habitat (SAL) beneficial uses. Salinity varies over time, but the available data indicate that the river should be considered saline. The U.S. Environmental Protection Agencys saltwater aquatic life criteria and saltwater California Toxics Rule (CTR) standards are being used to assess the SAL use for the Amargosa River. However, these criteria and standards are not really appropriate for assessment of inland saline waters. They were developed using marine and estuarine organisms, and inland saline waters support different aquatic biota. Inland saline water organisms are adapted to greater extremes of and fluctuations in environmental conditions than marine organisms. There are no state or federal aquatic life criteria for inland saline waters. One line of evidence, consisting of only two annual samples, is available to support this decision. There are not enough pH samples to establish baseline conditions (including diel, seasonal, annual and interannual variations) or to detect changes in the pH regime due to controllable factors, if such trends exist. This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. No biological data are available for assessment whether any of the chemical samples exceeds the water quality objective. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The data used do not satisfy the data quantity requirements of section 6.1.5 of the Policy (only one sample per year is available). 3. No biological data are available for assessment of compliance with the objective and the data cannot be evaluated using Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met. Regional Board Decision After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because no biological data are available for assessment of compliance with the objective.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because it cannot be determined if applicable water quality standards are not being exceeded. It is difficult to determine if the beneficial use is protected because the sampling is limited and there is no criteria to gauge compliance since the normal ambient pH level for this water body is unknown and so it is unknown whether any exceedence occured.

Line of Evidence (LOE) for Decision ID 30481, pH | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 33116
Pollutant: | pH
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Warm Freshwater Habitat
Number of Samples: | 0
Number of Exceedances: | 0
Data and Information Type: | PHYSICAL/CHEMICAL MONITORING
Data Used to Assess Water Quality: | There was 1 sample with a pH of 8.7. The normal ambient pH level for this water body is unknown and so it is unknown whether any exceedence occured.
Data Reference: | Statewide Perennial Streams Assessment 2008
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | The applicable objective states: "In fresh waters with designated beneficial uses of COLD or WARM, changes in normal ambient pH levels shall not exceed 0.5 pH units." (Lahontan Basin Plan).
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | Sample was collected at station 609PS0053 in Amargosa River.
Temporal Representation: | Sample collected on 5/14/2008.
Environmental Conditions: |
QAPP Information: | The SWAMP QAPP (2008) was followed.
QAPP Information Reference(s): | Surface Water Ambient Monitoring Program Quality Assurance Program Plan
Line of Evidence (LOE) for Decision ID 30481, pH | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46751
Pollutant: | pH
LOE Subgroup: | Pollutant-Water
Matrix: | Water
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 2
Number of Exceedances: | 0
Data and Information Type: | Fixed station physical/chemical (conventional plus toxic pollutants)
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled this station on on March 18, 2004 and March 16, 2005 under the Region 6 SWAMP program. Two sample both had pH values of 8.7 units..
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | .The Lahontan Basin Plan's objective for pH states: "In fresh waters with designated beneficial uses of COLD or WARM, changes in normal ambient pH levels shall not exceed 0.5 pH units. For all other waters of the region, the pH shall not be depressed below 6.5 nor raised above 8.5 units. The Regional Board recognizes that some waters of the Region may have natural pH levels outside of the 6.5 to 8.5 range. Compliance with the pH objective for these waters will be determined on a case-by-case basis."
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | Two samples were collected on March 18, 2004 and March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):

DECISION ID | 30793 | Region 6
Amargosa River (Willow Creek confluence to Badwater)

Pollutant: | Niobium
Final Listing Decision: | Do Not List on 303(d) list (TMDL required list)
Last Listing Cycle's Final Listing Decision: | New Decision
Revision Status | Original
Impairment from Pollutant or Pollution: | Pollutant
Regional Board Staff Conclusion: | This decision was moved to this waterbody (Amargosa River-Willow Creek confluence to Badwater) from the Amargosa River (Upper Canyon to Willow Creek confluence) as a correction during this listing cycle (i.e., decision placed on wrong waterbody or waterbody was mapped incorrectly in the past). This pollutant is being considered for placement on the section 303(d) list under section 3.1 of the Listing Policy. Under section 3.1 a single line of evidence is necessary to assess listing status. One line of evidence is available in the administrative record to assess this pollutant. There are no state or federal standards or criteria for niobium in sediment in inland saline waters. Based on the readily available data and information, the weight of evidence indicates that there is sufficient justification against placing this water segment-pollutant combination on the section 303(d) list in the Water Quality Limited Segments category. This conclusion is based on the staff findings that: 1. The data used satisfy the data quality requirements of section 6.1.4 of the Policy. 2. The single sample does not satisfy the data quantity requirements of section 6.1.5 of the Policy. 3. There are no applicable water quality standards or criteria and the data cannot be assessed using Table 3.1 of the Listing Policy. 4. Pursuant to section 3.11 of the Listing Policy, no additional data and information are available indicating that standards are not met.
Regional Board Staff Decision Recommendation: | After review of the available data and information, RWQCB staff concludes that the water body-pollutant combination should not be placed on the section 303(d) list because (1) the minimum sample number requirements of the Listing Policy are not met and (2) it cannot be determined if applicable water quality standards are being exceeded because there are no state or federal aquatic life criteria for inland saline waters or inland saline sediment, and (3) and the data are not temporally representative of the conditions in the river, which are characterized by great seasonal and annual variability in flows.

Line of Evidence (LOE) for Decision ID 30793, Niobium | Region 6
Amargosa River (Willow Creek confluence to Badwater)
LOE ID: | 46701
Pollutant: | Niobium
LOE Subgroup: | Pollutant-Sediment
Matrix: | Sediment
Fraction: | None
Beneficial Use: | Inland Saline Water Habitat
Number of Samples: | 1
Number of Exceedances: | 0
Data and Information Type: | Chemical monitoring of sediments
Data Used to Assess Water Quality: | The U.S. Geological Survey sampled sediment at this station on March 16, 2005 under the Region 6 SWAMP program. Results were reported as "bed sediment, smaller than 62.5 um, wet sieved, total digestion." The concentration of niobium was 15 ug/g dry weight.
Data Reference: | 2007. SWAMP Data for the Amargosa Hydrologic Unit
SWAMP Data: | SWAMP
Water Quality Objective/Criterion: | There are no state or federal standards or criteria for niobium in sediment in inland saline waters.
Objective/Criterion Reference: | Water Quality Control Plan for the Lahontan Region (as amended)
Evaluation Guideline: |
Guideline Reference:
Spatial Representation: | One station, Amargosa River below Willow Creek, was sampled.
Temporal Representation: | One sediment sample was collected on March 16, 2005.
Environmental Conditions: | The Amargosa River flows into California from Nevada and terminates in Death Valley. It is mostly ephemeral but there are perennial reaches. There is great seasonal and annual variability in flows. Most of the watershed is U.S. Bureau of Land Management or National Park land. The Amargosa River is not designated for the Municipal and Domestic Supply (MUN) beneficial use. The MUN use designation was removed in Basin Plan amendments that took effect in 2002. The rationale for removing the use included naturally high salinity and levels of toxic substances such as arsenic, and fluctuating water quantity that would make the river an unreliable supply if treatment were feasible. The perennial reaches of the Amargosa River and the associated riparian areas support a complex of rare, threatened or endangered fish and wildlife species. To Lahontan Water Board staffs knowledge, there are no salmonids in the river and there is no warm water fishery for human consumption.
QAPP Information: | The data meet the quality assurance requirements of the SWAMP QAPP.
QAPP Information Reference(s):